記述言語：英語   掲載種別：研究論文（学術雑誌）

In this study, in-situ synthesized stellate Mo2C reinforced WC/amorphous composite coatings have been prepared by resistance seam welding (RSW). The effects of WC-12Co amounts (0–30 wt%) on the microstructure, hardness, and wear properties of the composite coatings were performed using XRD, SEM-EDS, micro and nanoindentation techniques. The stellate Mo2C precipitates with a dispersion distribution were formed by the reaction between the carbon decomposed from WC-12Co and the Mo-rich region in the amorphous powder. The wear resistance of the C30 coating was 20.57 times that of the substrate respectively. The improved wear resistance was due to the metallurgical bonding between the uniformly distributed stellate Mo2C precipitates and the matrix, which weakened the adverse effects of WC peeling.

DOI： 10.1016/j.triboint.2023.108599

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記述言語：英語   掲載種別：研究論文（学術雑誌）

In this study, non equiatomic FeCrNiCoMoW MEA composite coatings were successfully prepared by electron beam cladding Fe-based amorphous powders. The effects of WC-10Co amounts (0–30 wt%) on the microstructure, mechanical properties, and electrochemical property of the MEA composite coatings were investigated. The added WC-10Co decomposed, and the original amorphous alloy was completely crystallised. The composite coatings primarily comprised the face-centred cubic (FCC) matrix, M23C6 (M = Cr, Mo, Fe, or W) and WC particles. The average hardness of the composite coatings gradually increased with increased WC-10Co amounts from 5.66 ± 1.09 GPa to 8.02 ± 2.54 GPa. The composite coating with 30 wt%WC-10Co showed optimal hardness and wear resistance, which were approximately 4 and 2 times that of the substrate, respectively. The wear mechanism changed from severe adhesive wear for 0 wt% WC-10Co composite coating to abrasive and slight adhesive wear for 10–30 wt% WC-10Co composite coatings. The 10 wt% WC-10Co coating exhibited the best corrosion resistance in 3.5 wt% NaCl solution. The number of corrosion pits decreased with the addition of WC-10Co increased, and corrosion occurred in the Cr-depleted regions. Solid solution, dislocation, WC particles and M23C6 nanoprecipitates were responsible for the improvement in mechanical properties and corrosion resistance of the coatings.

DOI： 10.1016/j.jallcom.2022.166882

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担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

<p>In this study, the CoCrNi medium entropy alloy (MEA) coating was firstly fabricated on 5083Al alloy by the resistance seam processing (RESP) method. After processing, the CoCrNi MEA powders were transformed into a simple face-centered cubic (FCC) structural coating with an average thickness of 381 ± 4 µm, and the heat-affected zone was rarely found in the Al alloy matrix. Furthermore, a certain amount of Al element penetrated into gaps of coating and Co, Cr and Ni elements were homogeneously distributed. The average hardness of the coating was 775 ± 68 HV_0.2, which was higher than the similar MEAs prepared by other reported methods. To evaluate its wear properties, the wear behaviors of CoCrNi MEA coating and 5083Al alloy were studied in detail. Although the main wear mechanisms of both materials were adhesive wear, the high hardness and plastic deformation ability of the MEA coating effectively improved its wear performance. Practically, the average wear rate was ∼10 times lower than 5083Al alloy. The RESP method was proved to be an effective method for preparing the high wear-resistance MEA coating on Al alloy.</p>

DOI： 10.2320/matertrans.mt-l2021018

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CiNii Research

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記述言語：英語   掲載種別：研究論文（学術雑誌）

The enhancement of wear resistance is a long-last changeling problem required by advanced application of Mg alloys. Herein, the lightweight TiC reinforced AlFeCrCo medium-entropy alloy (MEA) composite coating was firstly fabricated on Mg alloy via resistance seam processing. The coating was consisted of a BCC-based MEA matrix and TiC particles, in which a small amount of Mg (<5wt.%) penetrated into coating gaps. A good bonding between the coating and Mg alloy was formed, and such interface belonged to a semi-coherent relationship. Furthermore, a coherent interface between the MEA matrix and TiC was revealed with the crystallographic orientation relationships. Due to these well-bonded characteristics and reinforcing effects from TiC, this composite coating exhibited superior wear resistance by adhesive wear and oxidative wear. This work not only expanded the applicable types of coating materials, but also provided a novel method for preparing lightweight wear-resistant composite coating on Mg alloys.

DOI： 10.1016/j.scriptamat.2021.114429

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

To enhance the high-temperature oxidation performance of Ti-6Al-4V alloy, we successfully prepared a TiNiSiCrCoAl high-entropy alloy coating on its surface via laser cladding technology. X-ray diffraction, scanning electron microscopy, and electron probe microanalysis were used to characterize the microstructure, elemental distribution, and high-temperature oxidation resistance of the coating. The results indicated that the microstructure of the coating was composed of a matrix and a σ phase. Owing to the rapid cooling via laser processing and the matched δ, ∆Hmix, and Ω, the matrix phase was an amorphous structure rich in Ti, Si, Cr, and Co, and the σ phase was an FCC structure rich in Ti, Ni, Co, and Al. The volume fraction of the amorphous-structured matrix in the coating increased with increasing laser scanning speed. The section after the oxidation treatment was composed of an oxide layer, a transition layer, and a coating matrix. The oxide layer was composed of TiO2, Al2O3, and NiAl2O4, and the transition layer was rich in Si, Ni, and Co. The amorphous-structured matrix exhibited a higher oxidation resistance than the FCC-structured σ phase. Compared with the Ti-6Al-4V substrate, the oxidation resistance of the coating increased by 10.7, 28.1, 40.5, and 65.1 times at different laser scanning speeds under oxidation at 800 °C for 48 h, which indicates that the coating has better oxidation resistance than the Ti-6Al-4V alloy at high temperatures.

DOI： 10.1016/j.surfcoat.2022.128123

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

This study investigated the high-temperature oxidation behavior of a refractory NiSi0.5CrCoMoNb0.75 high-entropy alloy coating prepared via laser cladding technology. X-ray diffraction, scanning electron microscopy, and electron probe microanalysis were used to characterize the microstructure, elemental distribution, and high-temperature oxidation properties of the coating. The results show that the coating was composed of a matrix having the HCP structure, a lumpy σ phase with a rhombohedral structure, and a minor netlike μ phase having the FCC structure. After the coating was oxidized in air at high temperatures, the surface and cross-section of the oxide layer were analyzed. The results show that the oxide scale had a unique layered distribution. The oxide scale was subdivided into six banded layers according to the different alloying elements contained in each layer. The elements in the oxidation reaction were mainly Ni, Co, and Cr. Furthermore, the oxide scale was composed of Ni3(VO4)2, Ni3TiO5, NiCrO3, CoCr2O4, and Nb0.6Cr0.4O2.

DOI： 10.1016/j.jmrt.2022.01.115

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記述言語：英語   掲載種別：研究論文（学術雑誌）

In this study, WC-10Co/Ti-6Al-4V coatings were fabricated under varying cladding voltages via electron beam cladding technology. The microstructure, microhardness, and wear performance of the composite coatings were studied. In addition, temperature field simulations were performed for the cladding process applying ABAQUS. The thickness of the coatings ranged from 350 to 850 μm. The presence of α-Ti, (Ti, W)C1-X, and small amounts of WC, TiC, (W, Ti)C1-X, W2C, and β-Ti in the coatings was confirmed. WC and TiC were partially dissolved and, in accordance with the simulated temperature field, resulted in the appearance of (W, Ti)C1-X around the WC particles. Moreover, the consumption of C atoms was beneficial for the diffusion of W atoms into the TiC lattice to form (Ti, W)C1-X. In the comparison of experimental and numerical simulation results, it was found that a deeper penetration and further settlement of WC particles was observed experimentally, when a higher cladding voltage was applied. The coating prepared under 65 kV exhibited the best mechanical performance and its friction mechanism entailed abrasive and adhesive wear.

DOI： 10.1016/j.surfcoat.2021.127493

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記述言語：英語   掲載種別：研究論文（学術雑誌）

In this study, AlCoCrFeNiTi high-entropy alloy (HEA) coating was deposited on Ti-6Al-4V alloy by laser cladding, aiming at enhancing the high-temperature wear and oxidation resistance. The microstructure, hardness, oxidation performance as well as high-temperature wear of the coating were characterized respectively. The results indicated that the coating was composed of dendrite (DR) and interdendrite (IR) phases. The DR phase had FCC structure being rich in Al, Co, Ni and Ti. The IR phases had BCC structure, for which, the IR1 was rich in Fe and Cr, and the IR2 was rich in Fe, Cr, Ti, Co and Ni. The coating possessed much better oxidation resistance than Ti-6Al-4V alloy at 600 °C due to a more compact oxide surface and the sluggish diffusion effect, which impeded the subsequent oxidation effectively. The average oxidation rate of the coating was about one tenth that of Ti-6Al-4V alloy. Moreover, the oxide scale was about one fifth that of Ti-6Al-4V alloy. The average micro-hardness of the coating was 706.3 HV about 2.32 times that of Ti-6Al-4V alloy. The HEA coating exhibited a mixture wear mechanism of adhesive and oxidative wear at 600 °C, having a wear volume loss about one thirteenth that of Ti-6Al-4V alloy. 0.5

DOI： 10.1016/j.surfcoat.2021.127243

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記述言語：英語   掲載種別：研究論文（学術雑誌）

High performance Fe-based amorphous coatings were first fabricated on 304 stainless steel by resistance seam welding. The microstructure, microhardness, wear and corrosion resistance of the coatings under different welding current were systematically studied. The coatings consisted of amorphous phase and crystalline phases of M C , Fe C and α-Fe. Moreover, coating formation mechanism was characterized by welding temperature and microstructure variation of powders at different welding current. The dense amorphous coating was fabricated at about 750 K in welding current of 24 A and was seriously crystallized at 990 K in 30 A. The optimal hardness and wear rate of the coating reached 1280 HV and 2.71 × 10 mm /N·m, respectively, which exhibited better performance compared with the amorphous coating fabricated by the traditional methods. In 3.5 wt% NaCl solution, the corrosion resistance of all coatings was superior to that of the substrate, and corrosion occurred in the crystallization regions. As the welding current increased, the amorphous rate in the coating decreased, resulting in a decrease in the hardness, wear resistance and corrosion resistance of the coating. 23 6 3 0.1 −6 3

DOI： 10.1016/j.surfcoat.2020.126813

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記述言語：英語   掲載種別：研究論文（学術雑誌）

Previous studies have shown that sharp physical and chemical changes may induce the formation of swirl-like reaction phases in the ultrasonic spot welding (USW) of different materials. However, the mechanisms have not been well understood. In particular, swirl-like structures have seldom been discovered or discussed in the USW of Cu/Sn. In this study, swirl-like phases were observed in the USW of a Sn-coated T2 Cu plate with different welding energies (300−400 J). The evolution of the microstructure from the flat region to the swirl region was studied, the diffusion coefficient of Cu in Sn and the peak temperature of the interface during welding were theoretically calculated and experimentally verified, the formation mechanism of the swirl-like phases was discussed, and the relationship between the joint properties and welding energies was investigated. The results show that the content of Cu3Sn increases, while that of Cu6Sn5 decreases gradually from the flat region to the swirl region and that grain refinement of Cu and IMCs occurs near the swirl regions. The greatly enhanced diffusivity shows that intense atomic diffusion takes place during the welding process. When the welding energy exceeds 300 J, the experimentally measured peak temperatures in the welding processes are higher than the theoretical values. The formation of the swirl-like phase is attributed to the uneven distribution of interfacial stress and the collapse of cavitation bubbles. When the welding energy reaches 400 J, the peak lap shear load of the welded specimen reaches 1008 N, and the associated fractures indicate the combined characteristics of ductility and brittleness.

DOI： 10.1016/j.jmatprotec.2020.116911

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

We examined the effects of a nitrogen side-feed on the surface nitriding of a Ti plate. Surface nitriding of the Ti plate was performed by fiber laser irradiation, thus producing a hardened TiN layer. Two different nitrided areas (rough part and smooth part) could be formed on the surface of the Ti plate by changing the flow of the nitrogen. The roughness, microstructure, chemical composition, and phase composition of the two different nitride areas were analyzed with 3D-SEM, OM, XRD, EPMA, and EBSD. The cross-sectional microstructure, as observed, can be clearly divided into three parts: a modified layer which includes a film and a dendrite, a heat-affected zone (HAZ), and a substrate. In particular, the EBSD analysis shows that the crystal orientation of the smooth part is highly consistent, the preferential growth direction of the crystal is the main and the crystal grain size is large. The crystal orientation of the rough part is low in consistency, in addition to the preferential growth direction, other directions can also grow sufficiently, and the crystal grain size is small. The hardness test was performed on the cross-section of the nitride areas, revealing that the hardness of rough part and smooth part was 8 times that of the substrate.

DOI： 10.1016/j.rio.2020.100023

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担当区分：筆頭著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）

担当区分：筆頭著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2020 In this study, the AlFeCrCo medium-entropy alloy coating was first fabricated on a magnesium alloy using a resistance seam welding method. After welding, the AlFeCrCo medium entropy amorphous alloy powders were transformed into a body-centered cubic structure coating having an average thickness of 430 μm. The effect of instantaneous temperature on the formation ability of the coating was analyzed by theoretical calculations and experimental results. Based on the calculations, the instant Joule heating effect was only concentrated in the minute bonding area, and no direct or immediate increase in temperature occurred at the substrate. The experimental results demonstrated that the temperature gradient did not engender an obvious dilution of the matrix. The average microhardness of the coating (870 HV0.2) was approximately 12 times higher than that of the substrate. The wear performance was systematically evaluated in dry and 3.5 wt% NaCl solution conditions under different normal loads. Compared with the substrate and other high entropy alloy-related systems, the AlFeCrCo medium-entropy alloy coating exhibited good wear resistance. The wear resistance improved when the metal films and corrosive behavior were occurred in corrosive environments, which was anomalous to wear mechanism under dry conditions.

DOI： 10.1016/j.matdes.2020.108872

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担当区分：筆頭著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）

記述言語：中国語   掲載種別：研究論文（学術雑誌）

The (Ti, W)C1-x composite coatings were prepared on the surface of Ti-6Al-4V (TC4) alloy by high energy electron beam cladding technology using WC-10Co powder. The microstructure and phase composition of the composite coatings under different cladding currents were analyzed by SEM, EPMA and XRD, and the formation mechanism of each phase was discussed in detail. The microhardness and friction property of the composite coatings were analyzed by microhardness tester and ball-disk friction test equipment, and the friction mechanism of the composite coatings under different cladding currents was discussed. The results show that the WC powders in the three composite coatings were completely dissolved. The coating consists of α-Ti, β-Ti, dendritic and block (Ti, W)C1-x, and a small amount of W. The thickness of the coatings ranges from 400 to 600 μm, and the adhesion between the coatings and the substrate was good. Compared with the substrate, the average hardness and wear resistance of the composite coatings increased by 2~3 times and decreased with the increase of cladding current. The surface microhardness was up to 860 HV at the cladding current of 12 mA. In addition, the friction mechanism was abrasive wear at 12 mA and it became severer at 15 mA; at the cladding current of 18 mA, a little fatigue wear was also proved.

DOI： 10.11900/0412.1961.2019.00340

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2020 The continuous AlFeCrCoNi high entropy alloy coating was firstly fabricated on aluminium alloy by resistance seam welding. During welding, the coating was formed rapidly under the effect of instantaneous joule heating and the pressure. The gradient temperature transformed the nanocrystalline AlFeCrCoNi powder into the AlFeCrCoNi HEA coating consisted of body-centered-cubic and face-centered cubic structures. According to the calculation and experimental results, the welding process was not brought the negative affect to the substrate and only a certain amount of aluminum element penetrated into the coating. The average thickness and hardness of the coating were 420 µm and 715HV0.2, respectively. Compared to A6061, the coating exhibited excellent wear-resistance in dry, deionized water and 3.5 wt% NaCl solution conditions. The environment played an important role in the wear behaviour of the AlFeCrCoNi HEA coating. Meanwhile, the corrosive wear of the AlFeCrCoNi HEA coating was proved to be beneficial to reduce the wear rate.

DOI： 10.1016/j.apsusc.2020.145980

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2019 The Al0.8FeCrCoNi high entropy alloy coating (HEAc) was firstly fabricated on magnesium alloy by resistance seam welding (RESW) method. During welding, the Joule heating effect transformed the nanocrystalline HEA powder into a HEAc consisted of the face-centered cubic (FCC) and body-centered cubic (BCC) structures. The elements were homogeneously distributed and magnesium was found in the gap of HEAc. The wear properties of HEAc were studied systematically in dry, deionized water and 3.5 wt% NaCl solution conditions. Compared to AZ31, the HEAc exhibited good wear-resistance in dry and deionized water conditions.

DOI： 10.1016/j.matlet.2019.127250

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

<p>Mg-clad Al materials with a Ni foil interlayer were successfully prepared by vacuum roll bonding at a 450°C rolling temperature and 25% reduction, and the effects of the Ni foil interlayer on the interfacial properties were investigated. The clad materials with the Ni foil interlayer only formed the Mg₂Ni intermetallic compound with a 0.9 µm thickness on the Mg–Ni interface, which was smaller than that of the intermetallic compounds (Al₁₂Mg₁₇ of 1.77 µm and Al₃Mg₂ of 7.76 µm) formed on the Al–Mg interface without the interlayer. The bonding strength of the interface increased from 0.79 MPa to 10.46 MPa. The growth characteristics of the Mg₂Ni intermetallic compound on the Mg–Ni interface after heat treatment were investigated. The growth activation energy of Mg₂Ni was 157.24 kJ/mol, which is higher than that of Al₃Mg₂ which mainly affects the Al–Mg interfacial bonding strength. Therefore, the thickness of the Mg₂Ni was thinner and the interfacial bonding strength was greater after the vacuum roll bonding.</p>

DOI： 10.2320/matertrans.MT-M2019277

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CiNii Article

CiNii Research

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

<p>　The Al/Mg clad materials were produced by vacuum roll bonding. After bonding, the clad materials were heat treated at different temperatures. The growth of intermetallic compounds on Al/Mg bond interface was investigated. The results show that the growth of intermetallic compounds was very slow at 200℃ and only Al₃Mg₂ layer with 2 μm thickness was observed after 3h. Al₃Mg₂ and Al₁₂Mg₁₇ intermetallic layers were formed at and above 300℃, and the growth activation energy of Al₃Mg₂ (86.18 kJ/mol) is smaller than that of Al₁₂Mg₁₇ (115.33 kJ/mol), so the growth of Al₃Mg₂ is faster and thicker. The thickness of intermetallic layer has a great influence on the tensile strength of Al/Mg interface. When the thickness of the intermetallic layer exceeded 20 μm, the tensile strength reduced to less than 6 Mpa. After 200℃ heat treatment, ductile fracture and brittle fracture occurred simultaneously at Al/Mg interface during tensile test. After heat treatment at and above 300℃, the fracture of Al/Mg interface occurred in the intermetallic layer and mainly in the Al₃Mg₂ layer, and the mode of fracture were cleavage fracture.</p>

DOI： 10.11283/jlwa.58.107s

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CiNii Article

CiNii Research

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.34592/jlps.27.3_162

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）

In this study, pure HfO2 and Pr6O11-HfO2 coatings were prepared by atmospheric plasma spraying. The chemical compositions, morphologies, infrared radiation performances and thermal resistances of the coatings were characterized. The results showed that doping Pr6O11 could effectively improve the infrared emittance of the HfO2 coating. The HfO2 coating doping with 10 wt. % Pr6O11 exhibited the highest infrared emittance, which was 0.859 at room temperature and 0.883 at 1600 °C, correspondingly. This was mainly attributed to the oxygen vacancies, which created by the substitution of Hf4+ by Pr3+, could introduce localized energy states within the HfO2 band gap and increase the lattice distortion, producing lower symmetry vibrations. In addition, the Pr6O11-HfO2 infrared radiation coating possessed high tensile adhesive strength and good thermal resistance, which could withstand a high temperature treatment at 1700 °C for at least 50 h without exfoliation, and there was only a slight reduction in emittance. © 2019 Elsevier Ltd

DOI： 10.1016.2019.06.004

記述言語：英語   掲載種別：研究論文（学術雑誌）

In this study, pure HfO2 and Pr6O11-HfO2 coatings were prepared by atmospheric plasma spraying. The chemical compositions, morphologies, infrared radiation performances and thermal resistances of the coatings were characterized. The results showed that doping Pr6O11 could effectively improve the infrared emittance of the HfO2 coating. The HfO2 coating doping with 10 wt. % Pr6O11 exhibited the highest infrared emittance, which was 0.859 at room temperature and 0.883 at 1600 °C, correspondingly. This was mainly attributed to the oxygen vacancies, which created by the substitution of Hf4+ by Pr3+, could introduce localized energy states within the HfO2 band gap and increase the lattice distortion, producing lower symmetry vibrations. In addition, the Pr6O11-HfO2 infrared radiation coating possessed high tensile adhesive strength and good thermal resistance, which could withstand a high temperature treatment at 1700 °C for at least 50 h without exfoliation, and there was only a slight reduction in emittance.

DOI： 10.1016/j.jeurceramsoc.2019.06.004

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

© 2019 Published under licence by IOP Publishing Ltd. The A1050/AZ31 clad materials were produced by vacuum roll bonding. The effects of rolling temperature and reduction rate on the interface of A1050/AZ31 clad materials were investigated, and the fracture behaviors of A1050/AZ31 interface were studied. A very thin intermetallic compound layer was formed at the A1050/AZ31 interface at rolling temperature of 350°C and reduction rate of 25%. Therefore the A1050/AZ31 interface mainly was ductile fracture, and the average tensile strength of A1050/AZ31 interface reached the maximum (43MPa). When the rolling temperature was 450°C and the reduction rate was 25%, the fracture occurred on the brittle intermetallic compound Al3Mg2 layer (thickness 7.68μm) and Al12Mg17 layer (thickness 1.95μm), mainly on Al3Mg2 layer, and the average tensile strength of A1050/AZ31 interface reached the minimum (0.61MPa).

DOI： 10.1088/1757-899X/576/1/012031

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記述言語：英語   掲載種別：研究論文（学術雑誌）

We study the effects of hydrostatic pressure (HP) compression on the superconducting transition of severely strained Nb samples, whose grain sizes are reduced to the submicrometer level. Engineered granularity by high-pressure torsion (HPT) treatment changes the strength of coupling between submicrometer-scale grains and introduces lattice strain. We attempt to utilize the initially accumulated shear strain in the starting material for increasing the superconducting transition temperature T c under HP compression. The HP effects on non-strained Nb have already been investigated in the pressure regime over 100 GPa by Struzhkin et al. [Phys. Rev. Lett. 79, 4262 (1997)], and T c reportedly exhibited an increase from 9.2 to 9.9 K at approximately 10 GPa. (1) Slightly strained Nb in the HPT treatment exhibits the increase in T c under HP due to the strengthening of the intergrain coupling, so the pressure scale of the pressure response observed by Struzhkin et al. is reduced to approximately one-seventh at the maximum. (2) Prominently strained Nb in the HPT treatment exhibits the increase in T c under HP due to a reduction in structural symmetry at the unit-cell level: In a Nb sample subjected to HPT (6 GPa, 10 revolutions), T c exceeds 9.9 K at approximately 2 GPa. According to our first-principle calculations, the reduction in the structural symmetry affords an increase in the density of states at the Fermi energy, thereby yielding a prominent increase in T c at low pressures. © 2019 Author(s).

DOI： 10.1063/1.5083094

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2019 ISIJ. A project to develop Advanced Ultra-Supercritical (A-USC) power plant which operate at 700°C has been under way in Japan with the intension to reduce the CO2 emission and improve the power generation efficiency. Ni-based alloys, UNS N06674 (ASME Code Case 2826, 47Ni-23Cr-23Fe-7W, HR6W) and UNS N06617 (52Ni-22Cr-13Co-9Mo, Alloy 617) are candidate materials used in the high temperature regions of the A-USC power boilers. In this study, effect of creep degradation on the hardness change of both Ni-based alloys was investigated in order to evaluate the potential of the hardness method for creep life assessment. The investigation results showed that the scattering of hardness values in the latter stage of the creep life was increased as a result of hardening and softening of the material due to the increase of dislocation density with creep deformation and coarsening of precipitates followed by the formation of creep cavities, respectively. This tendency shows a good correlation with the creep life fraction. Therefore, it could be an useful tool for creep life evaluation. In addition, it was found that the hardness variation of the HR6W can be expressed as a function of temperature, stress and creep life fraction and thus leads to postulate a regression equation with hardness by a multivariate analysis. The creep life fraction can be calculated by substituting the values of service temperature and stress, and measured hardness into the multivariate regression equation. Those findings suggested that the hardness method was useful for the creep life assessment of Ni-based alloys.

DOI： 10.2355/isijinternational.ISIJINT-2018-878

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

For last half century the development of creep strength enhanced ferritic steels has been continued and presently ASME grades 91, 92 and 122 extremely stronger than conventional low alloy steels have extensively been used worldwide in high efficient power plants. However the use of these creep strength enhanced 9-12%Cr steels is limited to around 630°C or 650°C at maximum in terms of high temperature strength and oxidation resistance. Consequently the appearance of ferritic steels standing up to higher temperature of around 700°C to substitute of high strength austenitic steels is strongly desired. Under the state, the addition of high nitrogen to ferritic steels is attracting considerable attention because of improving high temperature strength and oxidation resistance of them. This work was done to evaluate the oxidation resistance of high nitrogen steels and to investigate the effect nitrogen and microstructure on oxidation resistance using 9-15%Cr steels with about 0.3% nitrogen manufactured by means of Pressurized Electro-Slag Remelting (PESR) method in comparison with ASME grades 91 and 122. As a result, high nitrogen ferritic steels showed excellent oxidation resistance comparing with nitrogen-free steels and ASME grades 91 and 122. The oxidation resistance of 9%Cr ferritic steels depends on the nitrogen content in the each steel. That is, the weight gain decreases with an increase in nitrogen content. Moreover, the oxide scale of high nitrogen steel contained a high concentration of Cr. It is conjectured that, in high temperature oxidation, nitrogen plays a key role in promoting the formation of the oxide scale which has high concentration of Cr, inhibiting oxidation from proceeding. And also it was found that the oxidation resistance of the high nitrogen steels does not depend greatly on Cr content but on their microstructure. The oxidation resistance of high nitrogen ferritic heat-resistant steels increased as the fraction of martensite structure increased. These results indicate for high nitrogen steels Cr diffusion along grain boundaries is further promoted resulting in the formation of protective oxide scale having high Cr concentration. Furthermore as new findings it was confirmed that the Cr diffusion in substrate of steels to form Cr concentrated oxide scale on the metal surface is accelerated by nitrogen while suppressed by carbon in matrix of steel.

DOI： 10.31339/asm.cp.am-epri-2019p0282

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記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2018 ISIJ. High temperature oxidation behavior of high nitrogen steel with about 0.3 mass% of nitrogen has been investigated comparing with nitrogen-free steels and ASME grade 91. High temperature oxidation tests were carried out in air over the temperature range 750 to 850°C for 300 h at maximum. Weight gain was measured and oxide scales were observed using an optical microscope and analyzed with an electron probe X-ray microanalyzer. It was found that the oxidation resistance of the high nitrogen steel is superior to that of nitrogen-free steels and ASME grade 91. Furthermore, Cr concentration in the oxide scale of the high nitrogen steel was higher than that in other steels. These results indicate high nitrogen promotes the formation of the oxide scale with high concentration of Cr inhibiting oxidation from proceeding in the high nitrogen steel.

DOI： 10.2355/isijinternational.ISIJINT-2018-246

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記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2018 ISIJ. Effect of Cr content and microstructure on high temperature oxidation behavior of high nitrogen steels with 0.2–0.3 mass% of nitrogen has been investigated. For high temperature oxidation test 9–15%Cr high nitrogen steels are prepared. High temperature oxidation tests were carried out in air mainly at 800°C for 300 h at maximum. Weight gain was measured and oxide scales were observed using an optical microscope and analyzed with an electron probe X-ray microanalyzer. The addition of high nitrogen improved the oxidation resistance of 9–15%Cr high nitrogen steels. It was found that the oxidation resistance of the high nitrogen steels does not depend greatly on Cr content but on their microstructure. The oxidation resistance of high nitrogen ferritic heat-resistant steels increased as the fraction of martensite structure increased. These results indicate for high nitrogen steels Cr diffusion along grain boundaries is further promoted resulting in the formation of protective oxide scale having high Cr concentration.

DOI： 10.2355/isijinternational.ISIJINT-2018-247

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2017 In this study, a double-layer Ti (C, N) film was successfully prepared on Ti-6Al-4V alloy by a series of YAG laser irradiation in nitrogen atmosphere, aiming at improving the wear resistance. The effects of laser irradiation pass upon surface chemical composition, microstructures and hardness were investigated. The results showed that the surface chemicals were independent from laser irradiation pass, which the up layer of film was a mixture of TiN and TiC 0.3 N 0.7 , and the down layer was nitrogen-rich α-Ti. Both the surface roughness and hardness increased as raising the irradiation passes. However, surface deformation and cracks happened in the case above 3 passes’ irradiation. The wear resistance of laser modified sample by 3 passes was improved approximately by 37 times compared to the as received substrate. Moreover, the cytotoxic V ion released from laser modified sample was less than that of as received Ti-6Al-4V alloy in SBF, suggesting the potentiality of a new try to modify the sliding part of Ti-based hard tissue implants in future biomedical application.

DOI： 10.1016/j.optlastec.2017.07.048

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記述言語：英語   掲載種別：研究論文（学術雑誌）

© 2017 Elsevier Inc. WC-Fe composite/metal coatings consisting of a WC-Fe composite layer and a metal interlayer were successfully fabricated on an Al 6061 substrate by resistance seam welding. The microstructures and phase compositions of the WC-Fe composite/metal coatings with different WC particle sizes (nano, fine, and coarse) were investigated. The WC-Fe composite layer consisted of WC particles and a Fe-C-Si super hard alloy (SHA) component, whereas the metal interlayer was composed of SHA, FeAl 3 , Fe 2 Al 5 , and Al 6061. The surface microhardness of the WC-Fe composite/metal coating increased with increasing WC particle size. The wear performance of the coatings tested with different sliding distances is discussed in detail. Coating-C (coarse) showed the best wear resistance. The wear rates of both coating-N (nano) and coating-C decreased as the sliding distance increased, while coating-F (fine) demonstrated the opposite behavior. The wear mechanisms of the coatings were drastically different owing to the significantly different WC particle behavior at various sliding distances.

DOI： 10.1016/j.matchar.2017.10.021

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担当区分：責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

The alloy development R & D activities for weld construction components, such as boiler piping and headers of high-efficient fossil-fired power plants have been conducted to introduce creep strength enhanced ferritic (CSEF) steels, grades 91, 92, 122, 911, 23 and 24 for last three decades. The grade 92 among these CSEF steels has the highest creep rupture strength to increase the steam temperature up to 620°C however the weld heat affected zone is much weaker in creep than the base metal due to the Type IV failure. Alloy design trials or proposal of the candidate steels in laboratory level has been conducted to improve the creep rupture strength than that of grade 92. Presently it is becoming possible in a very near future to introduce the new high strength ferritic steels beyond grade 92 on the commercial basis, and also the new steels could mitigate the Type IV failure at the welds to be applicable at the maximum use temperature of 625°C and above. But the creep degradation behavior in such new advanced steels is not yet well investigated and it is not verified that the creep degradation/life assessment techniques studied for the existing CSEF steels are applicable. Therefore the creep degradation and softening behavior of new advanced CSEF steels were studied and the hardness creep life assessment technique developed using grade 91 was applied to investigate the similarity of degradation process with the conventional CSEF steels. The present paper introduces the development status of new advanced steels beyond grade 92 in Japan and deals with the creep degradation and softening behavior of the new steels in comparison with grades 91 and 92.

DOI： 10.1115/ETAM2014-1007

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

真空圧延接合法は、真空中で熱間圧延することにより接合する方法である。この方法では、接合部界面における金属間化合物および酸化皮膜の形成を抑制し、良好な接合を得ることができる。本研究では、真空圧延接合法を用いて、金属間化合物を形成しやすい組み合わせのAlおよびCuの接合を行った。そして、得られたクラッド材の接合部における微細組織および接合部強さなどの接合性に及ぼす接合条件の影響について調査した。

DOI： 10.14920/jwstaikai.2017f.0_314

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CiNii Research

その他リンク： https://ci.nii.ac.jp/naid/130006259292

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）

DOI： 10.32163/amadareport.30.0_230

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130007994631

記述言語：英語   掲載種別：研究論文（学術雑誌）

A Ti(C, N)/TiB reinforced titanium matrix composite layer was successfully in-situ synthesized by laser melting on Ti-6Al-4V alloy surface with Ti-BN-C mixed powder, aiming at improving the wear resistance. The microstructure, chemical composition, hardness and wear behavior were analyzed. The results showed that, the cross sectional microstructure can be clearly divided into three parts, which were the laser melted layer, heat affected zone and non-affected zone. The reinforcements in laser melted layer consisted of dendritic TiC0.3N0.7 phases and fine-structure TiB phases. The matrix in laser melted layer was in a two-phase structure, being composed of platelet α titanium and intergranular β titanium. The hardness was increased from 320 HV in the substrate to 450-550 HV in the modified layer. The wear resistance was improved that, the wear volume loss of the laser treated sample was approximately half of the as received Ti-6Al-4V alloy after 8 h wear test.

DOI： 10.1016/j.optlastec.2016.01.004

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担当区分：責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（商業誌、新聞、ウェブメディア）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Copyright © 2016 Electric Power Research Institute, Inc.The creep degradation/life assessment for high temperature critical component materials is absolutely needed to assure the long-term service operation and there is little experience with the service exposure of the high temperature components made of newly developed Ni-based alloys. In this study, therefore, the creep degradation assessment study on the Ni-based alloys, Alloy 617 and HR6W was conducted based on the hardness method, because the hardness measurement is a useful and simple technique for the materials characterization for any kind of high temperatureserviced steels and alloys. As the result, it was found that the hardness was increased by not only precipitation due to thermal aging but also creep stress/strain, and there existed linear relationship between the applied stress and creep-induced hardness increase. Also the hardness scatter measured was increased along with the progress of creep hardening and damage progressing in terms of creep life consumed. Those findings suggested that the creep life assessment of Ni-based alloys would be possible by means of hardness measurement. The paper also deals with the role and perspective development of non destructive damage detecting techniques, and life assessment issues on Ni-based alloys for A-USC power applications.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Copyright © 2016 by ASME.The power plant materials engineers are still tweaking the specification of grade 91 in order to prevent the improper production and construction. In this sense the chemistry, heat treatment conditions and design/fabrication rules for this steel should be highly optimized to achieve the safe elevated temperature properties and to avoid the abuse during the construction. This paper presents the recent findings on creep degradation behavior in grade 91 followed by the review and discussion about the effect of chemical composition and constituent on the creep strength/ductility in correlation to the chemical specification for this steel. Additionally the design factor for creep and creep-fatigue of grade 91 steels was considered to propose a new rule on the stand point of the changes in creep degradation mechanism at long-term region. As the results it was found that the martensitic lath structure in the grade 91 exposed at the creep loading significantly reduces the dislocation density to form the ferritic subgrain structure at long-term exposure which exhibits different creep mechanism from that of original martensitic structure. So that the multiplier of 0.67 applied to average stress for rupture in 100.000 h may not be used even below the temperature of 815°C. Therefore the F-factor is recommended to be applied at the temperature above 615°C for base metal and 545°C for welds considering the magnitude of the creep strength scatter band in the existing chemical specification ranges.

DOI： 10.1115/PVP2016-63307

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

著者らは，SM490，板厚12mmのX形開先突合せ溶接について，経験上適当と考えるレーザ・アークハイブリッド溶接施工手順，開先形状および溶接条件を把握している．そこで，実機施工における溶接変形抑制の観点からこれら手順・条件の妥当性ついて数値解析による調査・検討を行った．

DOI： 10.14920/jwstaikai.2016f.0_328

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その他リンク： http://ci.nii.ac.jp/naid/130005435881

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

アルミニウムの拡散接合は鉄型又はチタン型と違い、接合過程において、接合界面に酸化被膜が存在するため、新生面の現出が妨げられ、十分な原子の拡散が生じず、低い接合強度しか得られないとされている。そこで、本研究において酸化被膜を破壊できるTLP拡散接合について検討した。

DOI： 10.14920/jwstaikai.2016f.0_276

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CiNii Research

その他リンク： http://ci.nii.ac.jp/naid/130005435804

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

レーザアークハイブリッド溶接によるSM490の突合せ溶接を対象として、マクロ断面・温度履歴をもとに熱弾塑性解析を行った。さらに、シミュレーションにより溶接変形に及ぼす開先形状の影響について検討した。

DOI： 10.14920/jwstaikai.2016s.0_124

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その他リンク： https://ci.nii.ac.jp/naid/130005169876

記述言語：日本語   掲載種別：研究論文（学術雑誌）

窒化処理法としては、塩浴窒化やガス窒化などがあるが、これらの処理方法は、特定部位のみを選択的に処理できない。そこで、本研究では、機械構造用炭素鋼の表面性能向上を目的として、処理時間が短く、局所的に、表面性能を改善できるYAGレーザ照射による鋼表面に窒化物改質層の形成法について検討した。

DOI： 10.14920/jwstaikai.2016f.0_74

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その他リンク： https://ci.nii.ac.jp/naid/130005435898

記述言語：英語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1080/09507116.2014.921063

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担当区分：責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1007/s40195-015-0210-3

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記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1016/j.surfcoat.2014.09.054

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記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1080/09507116.2012.753250

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記述言語：英語   掲載種別：研究論文（学術雑誌）

本研究ではTi-6Al-4V合金の耐摩耗性向上のため、炭素源としてレーザノンドロス371を合金の表面に塗布し、窒素及びアルゴンの混合ガスの雰囲気で、レーザ照射法によりチタン合金表面を未溶融或いは半溶融の状態に加熱し、チタン合金表面へのTi(C, N)層の形成について検討した。

DOI： 10.14920/jwstaikai.2015s.0_26

CiNii Article

その他リンク： http://ci.nii.ac.jp/naid/130005490283

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.7791/jspmee.4.79

CiNii Article

その他リンク： http://ci.nii.ac.jp/naid/130005119116

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.2320/matertrans.M2014242

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CiNii Article

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Germany   Stuttgart  

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.4028/www.scientific.net/AMR.941-944.2093

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記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.4028/www.scientific.net/AMR.941-944.2202

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Rome   Italy  

記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

In order to improve thermal efficiency of fossil-fired power plants through increasing steam temperature and pressure high strength martensitic 9-12%Cr steels have extensively been used, and some power plants have experienced creep failure in high temperature welds after several years operations. The creep failure and degradation in welds of longitudinally seam-welded Cr-Mo steel pipes and Cr-Mo steel tubes of dissimilar metal welded joint after long-term service are also well known. The creep degradation in welds initiates as creep cavity formation under the multi-axial stress conditions. For the safety use of high temperature welds in power plant components, the complete understanding of the creep degradation and establishment of creep life assessment for the welds is essential. In this paper creep degradation and initiation mechanism in welds of Cr-Mo steels and high strength martensitic 9-12%Cr steels are reviewed and compared. And also since the non-destructive creep life assessment techniques for the Type IV creep degradation and failure in high strength martensitic 9-12%Cr steel welds are not yet practically established and applied, a candidate way based on the hardness creep life model developed by the authors would be demonstrated as well as the investigation results on the creep cavity formation behavior in the welds. Additionally from the aspect of safety issues on welds design an experimental approach to consider the weld joint influence factors (WJIF) would also be presented based on the creep rupture data of the large size cross-weld specimens and component welds. Copyright © 2014 Electric Power Research Institute, Inc. Distributed by ASM International®. All rights reserved.

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記述言語：英語   掲載種別：研究論文（学術雑誌）

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

熱延工場のデスケーラ設備では高圧の水噴流による損傷が問題となる。そこで超硬合金と鋼をHIP法を用いてクラッドした複合材を適用して損傷対策とした。

DOI： 10.14920/jwstaikai.2014f.0_292

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005481718

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.11279/jfeskouen.164_98

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005311152

記述言語：日本語   掲載種別：研究論文（学術雑誌）

本研究では、真空圧延接合法によりA1050/AZ31/SS400クラッド材の作製を行い、A1050/AZ31及びAZ31/SS400の接合部の接合性、ミクロ組織及び引張強さに及ぼす接合条件の影響について検討した。

DOI： 10.14920/jwstaikai.2014s.0_144

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005473933

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.11279/jfeskouen.164_99

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005311156

担当区分：責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

本研究では抵抗クラッディング法により、板厚2mmのA6061合金板上に超硬質粉末WCと高炭素鋼粉末SHAの混合粉末を用いた耐摩耗性を有するクラッド層の形成とその形成メカニズムについて検討した。形成したクラッド層の断面のマクロ及びミクロ組織を観察した。また、XRD分析、ナノインデンテーション試験及びラバーホィール式摩耗試験を行った。

DOI： 10.14920/jwstaikai.2014s.0_152

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005473929

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.11279/jfeskouen.165_26

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005311107

記述言語：日本語   掲載種別：研究論文（学術雑誌）

軟鋼突合せ継手（板厚12mm）を対象にレーザ・マグハイブリッド溶接を用いて両側1パス溶接を行った．継手の健全性を放射線透過試験，継手引張および曲げ試験で確認したところいずれもJIS Z 3040の規定を満足した．また，マグ溶接に比べ，裏はつりが省略でき，パス数を減らすことができることを確認した．

DOI： 10.14920/jwstaikai.2014s.0_96

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005474085

記述言語：日本語   掲載種別：研究論文（学術雑誌）

高クロム鋳鉄を肉盛溶接した複合材が多用される。製品加工にプラズマ切断を用いると熱による変質や割れの発生で複雑形状への適用が困難である。本研究では熱による変質や割れを伴わないアブレッシブウオータージェット切断による高クロム鋳鉄肉盛溶接製耐摩耗複合製品の開発について検討した.

DOI： 10.14920/jwstaikai.2014s.0_136

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005473937

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

担当区分：責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（大学・研究所紀要）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

高炭素で溶接性が著しく劣る合金組成も粉末冶金手段によって製品化が可能となる. 特にHIP法を用いると温度と圧力の相乗効果で極めて緻密な焼結組織を得ることができる. 本研究では溶融溶接が困難な高炭素鉄基合金粉末をHIP法を用いて焼結を行い，その耐摩耗性について検討した.

DOI： 10.14920/jwstaikai.2013f.0.232.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10031178348

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10031173899

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1007/s40194-013-0028-4

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.2320/jinstmet.J2012070

Scopus

CiNii Article

記述言語：日本語   掲載種別：研究論文（学術雑誌）

HIP法で製作した硬質相分散型金属基複合材料の耐摩耗性を砂摩耗試験とエロージョン試験で評価した。砂摩耗試験では硬質相の割合とともに複合則にしたがって摩耗量が減少した。エロージョン試験では金属基材の摩耗と硬質相の脱落による摩耗量の増加が観察された。

DOI： 10.14920/jwstaikai.2013s.0.150.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10031138330

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.4028/www.scientific.net/AMR.602-604.2123

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.2207/qjjws.31.96

Scopus

CiNii Article

記述言語：日本語   掲載種別：研究論文（学術雑誌）

EN1563:2011に定められる固溶強化フェライト基地球状黒鉛鋳鉄は、一般的な球状黒鉛鋳鉄と比較して、溶接時の加熱過程における逆変態範囲が狭くなる事が明らかとなっている。本研究では、溶接熱影響組織形成に及ぼす各種影響因子の影響を調査した。

DOI： 10.14920/jwstaikai.2013s.0.194.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005046202

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.11279/jfeskouen.162_11

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005401431

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.11279/jfeskouen.163_109

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005401589

記述言語：日本語   掲載種別：研究論文（学術雑誌）

アルミニウム合金と鋼と溶接する際に、溶接界面に脆弱な金属間化合物が生成されるため信頼性の高い継手が得られない。そこで、本研究では、化学組成が異なるアルミニウム合金と一般冷間圧延鋼板SPCCとのスポット溶接部の組織および接合部強度に及ぼす接合条件および合金元素Mg，Si及びCuの影響を検討した。

DOI： 10.14920/jwstaikai.2012f.0.320.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10030687922

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10030687710

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

記述言語：英語   掲載種別：研究論文（学術雑誌）

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84860622603&origin=inward

記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

Siを多量に添加して基地組織をオールフェライトとした高強度球状黒鉛鋳鉄の強度特性に関する報告は幾つかあるが、溶接性に関しては殆ど研究されていない。そこで、この材料の熱影響部を検討するため、溶接熱サイクル再現試験を行い、金属組織の変化に及ぼす最高到達温度の影響を調査した。

DOI： 10.14920/jwstaikai.2012s.0.52.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10030121068

記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1179/1362171811Y.0000000088

Scopus

記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

高クロム鋳鉄の肉盛溶接で発生する溶接割れは「Stress-relief crack」と称して溶接層の剥離防止に有効な割れとされている。しかし、割れの周囲で摩耗が多いことや衝撃に対して弱い可能性が指摘されている。本研究では高クロム鋳鉄溶着金属の耐摩耗性に及ぼす溶接割れの影響について検討した。

DOI： 10.14920/jwstaikai.2012f.0.142.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005045702

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.11279/jfeskouen.161_121

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005401292

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10030150533

記述言語：英語   掲載種別：研究論文（学術雑誌）

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84887431607&origin=inward

記述言語：英語   掲載種別：研究論文（学術雑誌）

Pure titanium is a biocompatible material that is also useful in high-temperature environments, however, wear resistance of the pure titanium is weak. To improve the wear resistance of pure titanium, surface modification is performed using laser beam heating under various laser conditions. The modified surface layer produced by laser melting consists of titanium nitride (TiN), which improves the hardness and the wear resistance. However, the surface of this modified layer is not flat. In this study, the laser irradiation was performed in a controlled atmosphere and the effects of the atmosphere on the microstructure, hardness, and wear resistance of the irradiated region were investigated. As the pure titanium surface was heated by laser irradiation, a TiN film was formed on its surface without the introduction of cracks. A lamellar structure was also observed under the TiN film. The maximum TiN thickness obtained without cracking or peeling of the base metal was approximately 13 um. In comparison with the base metal, the hardness and wear resistance of the TiN film were approximately 8 and 22 times higher, respectively. © 2011 The Japan Institute of Metals.

Scopus

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

&nbsp;&nbsp;Pure titanium is a biocompatible material that is also useful in high-temperature environments, however, wear resistance of the pure titanium is weak. To improve the wear resistance of pure titanium, surface modification is performed using laser beam heating under various laser conditions. The modified surface layer produced by laser melting consists of titanium nitride (TiN), which improves the hardness and the wear resistance. However, the surface of this modified layer is not flat.<br> &nbsp;&nbsp;In this study, the laser irradiation was performed in a controlled atmosphere and the effects of the atmosphere on the microstructure, hardness, and wear resistance of the irradiated region were investigated. As the pure titanium surface was heated by laser irradiation, a TiN film was formed on its surface without the introduction of cracks. A lamellar structure was also observed under the TiN film. The maximum TiN thickness obtained without cracking or peeling of the base metal was approximately 13 &micro;m. In comparison with the base metal, the hardness and wear resistance of the TiN film were approximately 8 and 22 times higher, respectively.<br>

DOI： 10.2320/jinstmet.75.697

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10030260305

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.4028/www.scientific.net/AMM.117-119.984

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.4028/www.scientific.net/AMM.117-119.1895

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）

In order to develop wear resistant grizzly plates for sintered ore screening process, a commercial hypereutectic high chromium cast iron containing Nb and V carbides was surfaced by self-shielded tubular-cored arc welding to 32mm thick, 350mm wide and 1000mm long SS400 plates. First, Abrasive Waterjet (AWJ) machinability was investigated using the surfaced SS400 specimens of various thickness, then the abrasion resistance of the deposited metals and conventionally used material was reviewed. <br>&nbsp;&nbsp;The durability of the newly developed grizzly plates surfaced to 1000mm square SCW490 base metal and machined by AWJ was assessed under the impact and abrading of sintered ore, and compared with conventional cast plates. The main results obtained were as follows ; <br>&nbsp;&nbsp;(1) When surfacing was carried out with a single torch, transverse cracks generated considerably. On the other hand, the cracks reduced markedly with two-torch surfacing. <br>&nbsp;&nbsp;(2) The deposited metal showed good abrasion resistance. The AWJ maximum traverse rate however reduced to about half that of SS400 plate. <br>&nbsp;&nbsp;(3) AWJ machinability significantly reduced when the abrasive waterjets traversed across the cracks, forming uncut zones beneath the cracks by the deflection of the jets. <br>&nbsp;&nbsp;(4) The newly developed grizzly plates showed about four to six times more durability, while the conventional cast plates only last a couple of months. <br>&nbsp;&nbsp;(5) Presently, the newly developed grizzly plates are seen to be replacing conventional ones in the plant.

DOI： 10.11279/jfes.83.519

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10029579889

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10029336458

記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）

記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1080/09507111003655481

Scopus

記述言語：日本語   掲載種別：研究論文（学術雑誌）

チタンの溶融池挙動は、炭素鋼およびステンレス鋼の場合と異なることが知られている。この違いに着目しチタン溶融池の特性について、溶融池可視化装置による観察およびチタンの物性値に着目したコンピュータ熱流体解析によるモデリングを行ったので、その一例を紹介する。

DOI： 10.14920/jwstaikai.2011s.0.52.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10027949408

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.2320/jinstmet.75.166

Scopus

CiNii Article

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

DOI： 10.2207/qjjws.29.29

Scopus

CiNii Article

担当区分：責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：英語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

本研究は真空圧延接合法を用いて接合したアルミニウム/銅クラッド材の熱的安定性について調査するため、熱処理後のクラッドに対し、ミクロ組織観察、EPMA分析、XRD、EBSP解析および引張試験を行うとともに、金属間化合物の成長挙動および接合部の引張強さに及ぼす金属化合物の影響について検討した。

DOI： 10.14920/jwstaikai.2011f.0.38.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130004642356

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10030150371

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

Welding materials, that the principal chemical component is nickel, are used usually for the welding between copper and austenitic stainless steels. But many kinds of mechanical or physical properties of welds between two materials will change largely. In this study, Functionally Graded Piping Joints (FGPJ) have been manufactured as an experiment using copper and austenitic stainless steel (SUS304) powder by a process based on HIP. This composition has been confirmed by absorbed electron and characteristics X-ray images of each mixed layer for FGPJ to be uniform or continuous. The following items have been investigated and compared with the linear law of mixture rule: Vickers hardness, thermal expansion, and thermal conductivity at a one-dimensional non-steady state etc. Those physical properties have been identified to depend on the mixing ratios of copper and austenitic stainless steel (SUS304). Pretty good agreements have been obtained between the experimental data and the calculated values according to the linear law of mixture rule.

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=79952583350&origin=inward

記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

DOI： 10.2207/qjjws.28.383

Scopus

CiNii Article

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10026559108

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）

2010年07月12日  -  2010年07月14日

DOI： 10.4028/www.scientific.net/MSF.631-632.273

Scopus

記述言語：日本語   掲載種別：記事・総説・解説・論説等（商業誌、新聞、ウェブメディア）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

2010年04月  -  2010年04月

主要論文集（会議）

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

著者らは，既報でCFDを使ったトレーラ・シールト゛ホ゛ックス内のアルコ゛ン流れの調査結果を報告した。本報告では，ティク゛溶接トーチ・カ゛ス流れの影響を考慮したシミュレーション・モテ゛ルを考案し，アルコ゛ン流れを解析した。この結果，溶接トーチ・カ゛スからのアルコ゛ン流れがトーチとホ゛ックスの接続部付近のアルコ゛ン雰囲気に影響を与えていることが分かった。つまり，アルコ゛ン雰囲気全体を乱すものではないが，その部分で少し大気が混入し，アルコ゛ンが希薄な空間が存在することを確認した。

DOI： 10.14920/jwstaikai.2010f.0.192.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130004642027

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.11279/jfeskouen.157_75

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005400883

記述言語：日本語   掲載種別：研究論文（学術雑誌）

工業用純アルミニウム板に銅製のスタッドボルトを溶接し、その溶接性について調査した。溶接にはCDスタッド溶接機を用いて、コンデンサー容量及び充電電圧の溶接条件を変化させてスタッド溶接を行い、溶接部のミクロ組織観察、元素分析及び引張試験を行った。また、引張破断面のSEM観察およびX線回折を行い、接合部界面における金属間化合物の形成の有無についても調査した。

DOI： 10.14920/jwstaikai.2010f.0.51.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130004642069

記述言語：日本語   掲載種別：研究論文（学術雑誌）

DOI： 10.11279/jfeskouen.156_109

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005400538

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

In structural materials, it is investigated to make crystal grain size less than 1μm in order to improve strength and toughness. Authors reported that fine ferrites were obtained by laser irradiation in steel. However, it is not made clear that an effect of laser irradiation on the materials which do not have a transformation. In this study, we performed laser irradiation for austenite stainless steel SUS304 as the materials which did not have a transformation and investigated an effect of laser irradiation on grain refinement. Solution treatments were performed for SUS304 and their initial grain size became 23 and 68μm. Then they were given four kinds of strain ε and irradiated laser under some laser traveling speeds v and some defocus distances fd. As the result, they became recrystallization grain and their size were obtained about 10 and 15 μm, for initial grain size respectively, under the best condition (laser power=1.5kW, fd=60mm, v=350 mm/min, ε= 40%). Then a recrystallization grain size was caused by each factor of laser traveling speed (heating temperature, heating time), strain and defocus distance. Furthermore, as an electro-gas arc weld of SUS304, the grain size was 40μm in heat affected zone, was irradiated after shot peening, it was clarified that fine grain was obtained from 10 to 15μm at the heat affected zone.

DOI： 10.2207/qjjws.27.270

Scopus

CiNii Article

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記述言語：英語   掲載種別：研究論文（学術雑誌）

The refinement of ferrite grain of ultra low carbon steel was observed in cyclic laser irradiation. The high heating and cooling rates were considered to cause the promoted nucleation and the suppressed grain growth. The process of refinement of grain during the laser irradiation was investigated by Monte Carlo simulation. In order to obtain the accurate simulation, the apparent activation energy of austenite grain growth was measured by isothermal heating experiments and used in the simulation of austenite grain growth. The results of the austenite grain growth simulations had a good agreement with the experimental results. Consequently, α ⇆ γ phase transformations which involved temporal and spatial heterogeneous nucleation were modeled with Monte Carlo method in order to simulate the process of the cyclic laser irradiation. The phase transformed fraction of ferrite and austenite with high heating and cooling rates were also obtained by simulation, and the curves of transformed fraction of ferrite and austenite showed sigmoidal variations with temperature. The results of the simulations showed the decrease of ferrite and austenite grain size with increase of times of the cyclic laser irradiation, which could explain the refinement of ferrite grain by the cyclic laser irradiation.

DOI： 10.2207/qjjws.27.89

Scopus

CiNii Article

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記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

主要雑誌

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

CiNii Article

記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

It is known that it is difficult to bond dissimilar metals such as aluminum and copper or aluminum and iron using diffusion bonding, because an intermetallic compound is easily produced at the bond interface and bonding strength becomes low. However it is possible to bond the dissimilar metals using the vacuum roll bonding which performs hot rolling in a vacuum. In this study, we investigated the effect of bonding temperature and reduction of aluminum plate thickness on bonding strength of Al/Cu clad materials when aluminum-clad copper (Al/Cu clad) materials were produced at 3 Pa in vacuum degree by the vacuum roll bondings. Bond tensile strength of Al/Cu clad materials increased as the reduction was increased. Their fracture types were classified according to the fracture pass, that is, in the base metal of the aluminum, at the bond interface of Al/Cu clad material or in the base metal and/or at the bond interface. Furthermore, the bond interfaces of Al/Cu clad materials were observed using a transmission electron microscope and an electron dispersive spectroscopy. As a result, it was clarified that Al/Cu clad materials are soundly produced using the vacuum roll bonding when thickness of diffusion layer is less than 60 nm even if intermetallic compounds were developed.

DOI： 10.2464/jilm.59.542

Scopus

CiNii Article

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

A crystallography study and observation of microstructure were carried out on the joint of an Au ball and Au electrode formed using two modes of ultrasonic bonding which show differences under the life test. A non-bonded joint was seen on the samples using SEM observation. Also, it was found that the length of bonding of the LP sample, which was bonded using low ultrasonic output, was short compared with that of the HP sample, which was bonded using high ultrasonic output. From an analysis of the IPF image obtained using EBSD, the interface of the joint in the LP sample apparently retained the crystal orientation of the interface before bonding. However, {001} in the HP sample, the crystal grain formed parallel to the bonded plane in the newly formed large area without obvious interface from the joint. It was concluded from this that the crystal grain having the same axis as the Au ball formed in the Au electrode though the orientation was not obvious from SEM and TEM observation.

DOI： 10.5104/jiep.12.307

Scopus

CiNii Article

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記述言語：英語   掲載種別：研究論文（学術雑誌）

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

The γ→α transformation during continuous cooling was simulated by Monte Carlo method on conditions of ten stages of cooling rate and nine stages of austenite grain sizes. The authors have investigated effects of cooling rate and initial austenite grain size on γ→a transformation and ferrite grain growth. Main results obtained are as follows. The relationship between ferrite grain sizes and cooling rate showed that the ferrite grain sizes hyperbolically decreased against the cooling rate until 500°C/s and then the ferrite grain refinement hardly occurred. The ferrite grain sizes were decreased with an decrease of the initial austenite grain sizes. γ→α transformation rate was increased with the refinement of initial austenite grain. A linear relationship between initial austenite grain sizes and final ferrite grain sizes was obtained by simulation of continuous cooling. © 2009 The Japan Institute of Metals.

DOI： 10.2320/jinstmet.73.495

Scopus

CiNii Article

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

担当区分：責任著者   記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：日本語   掲載種別：研究論文（学術雑誌）

溶融溶接を利用した複合化に関しては、鋼製母材に異種材料を溶接肉盛する方法が一般的であるが、鋳鉄を鋼製母材に溶接肉盛した例は極めて少ない。本研究では、鋳鉄と鋼の溶融溶接に必要な予熱を溶接ビードの伝導熱を利用する方法で与えて溶接肉盛を行ない、得られた溶接金属の性質を調査した。

DOI： 10.14920/jwstaikai.2009f.0.95.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130004641919

記述言語：日本語   掲載種別：研究論文（学術雑誌）

エチレン分解炉管に使われる耐熱遠心鋳鋼管(25Cr－35Ni鋼)を局部強制浸炭処理した試験片を用い浸炭現象による超音波音速変化を調べた結果、浸炭量の増加とともに超音波音速値が増加する傾向が認められた。これにより、未浸炭部と浸炭部の音速変化量を測定し、浸炭層深さを評価する手法を開発した。

DOI： 10.14920/jwstaikai.2009f.0.56.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130004641876

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1080/09507110802410643

Scopus

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記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

記述言語：英語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110007059700

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）

東京   2008年06月10日  -  2008年06月12日

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

2007年度

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：日本語   掲載種別：研究論文（学術雑誌）

<I>超音波接合は半導体組立に広く適用されている。Auボール／Au電極接合部の接合トラブルにおいて、接合部の結晶組織についてほとんど調べられていない。そこで、Au／Au接合部の結晶組織に注目して詳細に調べた。 接合前のAuボールとAu電極の結晶方位は接合面に<001>と<111>を示した。接合後は<001>に変わり、超音波により変化したものと考えられる。また、Au／Au接合層の厚さは0.5μm程度で、結晶方位は接合面に<001>を示し、その長さによって接合強度と耐久試験に差が生じることがわかった。</I>

DOI： 10.11486/ejisso.22a.0.173.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130004589215

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌 代表的研究業績

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

Laser surface modification method for pure titanium plate was performed using nitrogen gas as a shielding gas. The laser fusion layer obtained was investigated using the metallurgical analysis, a hardness test and an abrasion test. In the microstructure of the laser fusion layer, primary dendrite of TiN and eutectics composed of Ti and TiN were observed regardless of shielding gas flow rate. The Vickers hardness of the laser fusion layer increased with the increase in the shielding gas flow rate, and the laser fusion layer had the maximum Vickers hardness number of 1040 HV when a shielding gas flow rate was 40 L/min. As the abrasion property of the laser fusion layer in the shielding gas flow rate of 20 L/min was compared with that of the base metal TP270H, the wearing width of the laser fusion layer was decreased 50% below that of the base metal. In addition, the wear coefficient of the laser fusion layer became about 17% in comparison with that of the base metal.

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

記述言語：日本語   掲載種別：記事・総説・解説・論説等（その他）

記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1080/09507110701579613

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（学術雑誌）

The thermal sprayed coatings are widely used in waste incineration boilers and fossil fuel-fired boilers. However, the defects, such as porosity, cracks and unmelted particles, in these coatings are detrimental to corrosion performance. In this study, the nickel based self fluxing alloy coating was fused by YAG laser to improve performance of the coating. Under appropriate laser parameters, the nonporous, crack-free coating was produced. The rubber wheel type abrasion wear test and hot corrosion test conducted in the presence of a mixed salt of Na2SO4/NaCl/KCl at 650°C showed that the modified coating exhibited excellent wear and corrosion resistances compared with the as sprayed and gas fused coatings.

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

Lap resistance spot welding was performed on cold rolled steel (SPCC) with an electrode force changeable lap resistance welding machine the authors had developed. We evaluated the welds by ultrasonic testing (immersion method, C-scope representation) and a tensile shear test, and compared the results for this method with those by the conventional method. It was useful to apply the ultrasonic testing to evaluate the welds. Usually plug-type fracture was observed in the tensile shear test and the maximum tensile shear load was larger than those estimated using the value of the minimum strength (290 MPa) of SPCC specified by the Japanese Industrial Standard, though some specimens fractured along the weld interface. Regression analysis was performed by setting the maximum tensile shear load as a dependent variable, and setting the initial electrode force, the welding current, the initial electrode force timing and the latter electrode force as independent variables. The result shows that only the initial electrode force and the welding current were significant. The maximum tensile shear strength increased by increasing the welding current and decreasing the initial electrode force. It was made clear that we could obtain better spot welds by using the process we developed than the convcntional spol welds.

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

The thermal sprayed coatings are widely used in waste incineration boilers and fossil fuel-fired boilers. However, the defects, such as porosity, cracks and unmelted particles, in these coatings are detrimental to corrosion performance. In this study, the nickel based self fluxing alloy coating was fused by YAG laser to improve hot corrosion resistance of the coating. Under appropriate laser parameters, the nonporous, crack-free coating was produced. Hot corrosion test, conducted in the presence of a mixed salt of Na2SO4/NaCl/KCl at 550°C, showed that the modified coating exhibited excellent corrosion resistance compared with the as sprayed and gas fused coatings.

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

They developed CMT process in Fronius with which it is possible to perform fusion welding (they call as arc brazing) between zinc plated steel sheet and aluminum alloy sheet. We applied this process to perform welding between zinc plated SPCC (thickness of zinc: 7-22 μm) and A5052-O sheet (thickness: 0.8 mm) with a filler wire of A4043, and first examined the change in the thickness of zinc plated layer in HAZ. In the region from 400 to 800 μm from the toe into HAZ the thickness tended to decrease but recovered the original thickness after that. EPMA result shows that zinc distributed in the weld metal over the region about 30 μm near the weld interface and this should be dissolved in the weld metal. TEM result shows that the intermetallic compound layer of about 1 μm thickness was developed near the weld interface and made clear that these composed of Al13Fe4, Al3Fe2Si and Fe2Al3. Finally, the fracture occurred in the base metal of A5052 when we performed a tensile shear test on the welded joints and this showed that we could obtain good welded joints between zinc plated SPCC and A5052 through CMT process.

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

Resistance spot welding has been widely used in the field of automobile industry. The authors have developed a resistance spot welding machine by which electrode force can be easily changed during weld time. We studied the influence of electrode force (base electrode force P 0, primary electrode force P 1 and secondary electrode force P 2 and welding current I in spot welding on the properties of welds of aluminum alloy AA6022-T4 which is used in the automobile industry. We changed welding current and electrode force, and monitored temporal changes of electrode forces during the welding. Shapes of the temporal changes of electrode force monitored were classified in three kinds and these lead to the changes of the maximum tensile shear load F max of welds. Though some solidification cracks were observed in the thickness direction of specimens when welding currents and electrode forces were high, these did not affect the maximum tensile shear loads because sufficiently large nuggets were developed. Solidification cracks parallel to the specimen surface, however, lead to the decrease in F max. The results by regression analysis of the influence of P 0, P 1, P 2 and I on F max showed that F max increased with the increase in P 1 when P 0 = 2450 N but increased with the decrease in P 1 when P 0 = 3000 and 3430 N for the same welding current, and no influence of P 2.

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

Ni基自溶合金溶射皮膜にレーザフュージングを行った皮膜は、Crのホウ化物及び炭化物を内在する微細な組織となり、硬さが上昇した。レーザフュージング条件fd=45mmにおいて耐摩耗性は最も向上した。これは皮膜組成の変化が生じずフュージングの効果が最も効果的に得られるためと考えられる。

DOI： 10.14920/jwstaikai.2006f.0.158.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10017533624

記述言語：英語   掲載種別：研究論文（学術雑誌）

本研究では、シーム溶接機を用いた抵抗クラッディング法を用い、対摩耗粉末としてWC,WC-6.5Coを用いてクラッド化が可能であるか検討した。その結果、WCの試料で母材内のFe元素、WC-6.5Coでは母材内のFe元素、粉末中に含まれるCo元素によってクラッド層を形成することを確認した。

DOI： 10.14920/jwstaikai.2006f.0.161.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10017533628

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌 代表的研究業績

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

We hold many expectations that aluminum-clad steel will be applied for functional material, structural transition joint for welding steel structure to aluminum structure and so on. In this study we investigated the effects of aluminum purity and/or bonding conditions, which were bonding temperature, reduction rate of aluminum plate thickness (R Al), vacuum degree, on bond tensile strength of aluminum-clad steels produced by the vacuum roll bonding. And also the bond interfaces were observed using a high-resolution transmission electron microscope (RE-TEM). When A1050/SS400 clad materials, which produced at more than 450°C in bonding temperature, more than 17% in R Al and less than 10 Pa in vacuum degree, were performed in tensile test, they fractured through base metal of the aluminum. The values of bond tensile strength were obtained over 100 MPa. The bond tensile strength of 4N-Al (99.99 mass%Al)/SS400 clad material, which produced at 500°C in bonding temperature, 20% in A Al and 3 Pa in vacuum degree, was obtained about 80 MPa and test piece fractured through base metal of the aluminum. In the analysis results for bond interface of A1050/SS400 clad materials (5001 in bonding temperature, 20% in R Al and 3 and 10 Pa in vacuum degree) using a HR-TEM and an electron dispersive spectroscopy (EDS), no intermetallic compound and continuously amorphous phase in thickness from 2 to 3 nm were observed. The composition of the amorphous phase consists of mostly Al, O, Fe and Si. For the bonding interface of 4N-Al/SS400 clad material (500°C in bonding temperature, 20% in R Al and 3 Pa in vacuum degree), amorphous phase and nano-crystal were observed using HR-TEM. Therefore, it was clarified A1050 and 4N-Al/SS400 clad materials obtained using a vacuum roll bonding were bonded through the amorphous phase.

Scopus

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10022564002

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）

主要雑誌

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

CMT溶接を適用すると、これまで不可能とされてきたAlと鋼の接合が可能となってきた。本研究では、本方法を亜鉛メッキ層の厚さを変化させた鋼材とAlの溶接に適用し、メッキ層の挙動及び金属間化合物の形成の有無、界面近傍の亜鉛の分布及びTEM観察、並びに引張せん断試験時の特性について検討した。

DOI： 10.14920/jwstaikai.2006s.0.62.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110005857313

記述言語：英語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110005857368

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10017977552

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

Lap resistance spot welding was performed on cold rolled steel (SPCC) with an electrode force changeable lap resistance welding machine the authors had developed. We evaluated the welds by ultrasonic testing (immersion method, C-scope representation) and a tensile shear test, and compared the results for this method with those by the conventional method. It was useful to apply the ultrasonic testing to evaluate the welds. Usually plug-type fracture was observed in the tensile shear test and the maximum tensile shear load was larger than those estimated using the value of the minimum strength (290 MPa) of SPCC specified by the Japanese Industrial Standard, though some specimens fractured along the weld interface. Regression analysis was performed by setting the maximum tensile shear load as a dependent variable, and setting the initial electrode force, the welding current, the initial electrode force timing and the latter electrode force as independent variables. The result shows that only the initial electrode force and the welding current were significant. The maximum tensile shear strength increased by increasing the welding current and decreasing the initial electrode force. It was made clear that we could obtain better spot welds by using the process we developed than the conventional spot welds.

DOI： 10.2207/qjjws.24.10

Scopus

CiNii Article

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記述言語：英語   掲載種別：研究論文（学術雑誌）

The authors have developed an apparatus for varying an electrode force of a spot welding machine. This is equipped with a servomotor by which we can change rotation instantaneously from normal to reverse and vice versa, and also has a display by which we can monitor the change in the electrode force. Lap resistance spot welding was performed on cold rolled steel (SPCC) and temporal changes of the electrode force were compared with those by a conventional process. In the conventional process the electrode force changed complexly with the elapsed time and the changes were divided into three kinds depending on welding current. When we decreased the initial electrode force than that in the conventional process good welds could be obtained even in lower welding current and the decrease in the thickness of the welds could be lowered. In this case the temporal changes of the electrode force could be explained during the expansion and shrinkage of the welds, though the electrode force changed complexly depending on the initial electrode force and welding current.

DOI： 10.2207/qjjws.24.3

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

Ni基自溶合金は、一般的にガスフュージングを施して溶射皮膜本来の性質を改善して使用されている。そこで、レーザ照射を行い、従来のガスフュージング材との比較を行うことにより、レーザ照射材の耐摩耗や耐腐食性に優位性について検討を行った。

DOI： 10.14920/jwstaikai.2006s.0.49.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005045311

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

We hold many expectations that aluminum-clad steel will be applied for functional material, structural transition joint for welding steel structure to aluminum structure and so on. In this study we investigated the effects of aluminum purity and/or bonding conditions, which were bonding temperature, reduction rate of aluminum plate thickness (RAl), vacuum degree, on bond tensile strength of aluminum-clad steels produced by the vacuum roll bonding. And also the bond interfaces were observed using a high-resolution transmission electron microscope (RE-TEM).<br>When A1050/SS400 clad materials, which produced at more than 450&deg;C in bonding temperature, more than 17% in R_Al and less than 10 Pa in vacuum degree, were performed in tensile test, they fractured through base metal of the aluminum. The values of bond tensile strength were obtained over 100 MPa. The bond tensile strength of 4N-Al (99.99 mass%Al) /SS400 clad material, which produced at 500&deg;C in bonding temperature, 20% in R_Al and 3 Pa in vacuum degree, was obtained about 80 MPa and test piece fractured through base metal of the aluminum. In the analysis results for bond interface of A1050/SS400 clad materials (500&deg;C in bonding temperature, 20% in R_Al and 3 and 10 Pa in vacuum degree) using a HR-TEM and an electron dispersive spectroscopy (EDS), no intermetallic compound and continuously amorphous phase in thickness from 2 to 3 nm were observed. The composition of the amorphous phase consists of mostly Al, O, Fe and Si. For the bonding interface of 4N-Al/SS400 clad material (500&deg;C in bonding temperature, 20% in R_Al and 3 Pa in vacuum degree), amorphous phase and nano-crystal were observed using HR-TEM. Therefore, it was clarified A1050 and 4N-Al/SS400 clad materials obtained using a vacuum roll bonding were bonded through the amorphous phase.

DOI： 10.2207/qjjws.24.215

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130004445482

記述言語：日本語   掲載種別：研究論文（学術雑誌）

抵抗シーム溶接法の原理を応用して、厚さ２mmSPCCの上に耐摩耗性材料の混合粉末をクラッディング材料として使い、耐摩耗性表面改質層を形成した。そして、そのクラッド層の耐摩耗性を評価した。

DOI： 10.14920/jwstaikai.2006s.0.117.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130005045263

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

奈良   2005年11月30日  -  2005年12月02日

主要論文集（会議）

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌 代表的研究業績

記述言語：英語   掲載種別：研究論文（学術雑誌）

This study deals with the performance of a 1 mm-thick wear resistance cladding layer of composite metal powder of 110-160 μm-sized STL-1(Co-Cr alloy) and 100 μm-sized MBF-15 (Ni based brazing alloy) applied by the resistance welding method to clad 1.9 mm-thick mild steel plate. Two metal powders were prepared as the cladding materials, in the ratio of two to one by weight. We studied the microstructures and results of EPMA of cladding layers to obtain the most suitable joint conditions. Also, bending and abrasion tests were performed to evaluate the bondability with the substrate and the wear behaviour of the cladding layer. The main results obtained are as follows: The wear resistance cladding layer had sound microstructures when it had been applied under the following welding conditions: welding current higher than 2.1 kA, welding speed of 1.0 m/min, and electrode force less than 392 N. In spite of cracks occurring in the cladding layer after the bending test, the cladding layer, applied under almost all welding conditions, was not separated from the substrate. We obtained the wear behaviour of the mild steel, 16.833 mg/min-wear loss and 0.046 mm/min-abrasion depth. The characteristics of the cladding layer, which had been applied with welding conditions - welding current of 2.5 kA, welding speed of 1.0 m/min, and electrode force of 196 N, had a satisfactory wear resistance behaviour of 15.726 mg/min-wear loss and 0.043 mm/min-abrasion depth.

DOI： 10.1007/BF03266493

Scopus

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

Pure titanium has an excellent biocompatibility in comparison with stainless steels and Ti-Al-V alloys. We would expect pure titanium to have application for artificial joints and artificial bones if the wear resistance of the pure titanium were to be improved. So the surface modification of the pure titanium was performed using YAG laser beam. The laser power was 1.5 kW and Ar was used as the shielding gas. The shielding gas flow rate was changed from 5 to 40 L/min with a constant laser torch traveling speed of 500 mm/min. First, we investigated effects of the shielding gas flow rate on the Vickers hardness of the laser melted zone. When the shielding gas flow rate decreases, the average hardness increases and the oxygen and nitrogen concentrations of the laser melted zone also increase. We made clear the relationship between the average hardness and the nitrogen equivalent in the laser melted zone as follows. When the square root of the nitrogen equivalent (N eq = N+ O/2) was less than 0.1, a plot of the average hardness for the square root of the nitrogen equivalent reveals a linear relationship. However, the average hardness of the laser melted zone increased more than the value indicated by the linear relationship when the square root of the nitrogen equivalent was above 0.1. Next, metallurgical analyses of the laser melted zone were performed using an electron probe micro analyzer (EPMA), an X-ray diffraction method (XRD) and a transmission electron microscope (TEM), and effects of the behavior of oxygen and nitrogen on the hardness of the laser melted zone were studied. A uniform dislocation structures in the laser melted zone is observed over a wide area where there is the linear relationship between the hardness and the square root of the nitrogen equivalent. Lamellar structure, which alternated between two phases of αTi and TiN in the laser melted zone, was formed where the hardness is greater than those indicated by the linear relationship. One phase of TiN contained a large quantity of nitrogen, and the other phase of αTi contained little nitrogen. It is found that the lamellar structure composes of αTi and Ti-nitrides (TiN and TiN 0.26). It is also observed that a wide area of αTi possesses a twin structure with a high dislocation density. © 2005 The Japan Institute of Metals.

DOI： 10.2320/jinstmet.69.509

Scopus

CiNii Article

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記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

We tried to bond two dissimilar combinations, 5052/SUS304 and 5052/SPCC, by ultrasonic spot bonding. The bondability of bonds was evaluated by performing ultrasonic testing and tensile shear test. In principle, good bonding was obtained by ultrasonic bonding without developing any intermetallic compounds. A good correlation between results of ultrasonic testing and tensile shear test could be obtained by selecting the appropriate threshold level in the ultrasonic testing. The microstructure in nano-scale order was observed near the bond interface using TEM to make clear the mechanism of the bonding. We could notice that amorphous structure was developed near the bond interface and this contributed the good bonding of the dissimilar materials by ultrasonic bonding.

DOI： 10.2207/qjjws.23.194

Scopus

CiNii Article

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌 代表的研究業績

記述言語：日本語   掲載種別：研究論文（学術雑誌）

ごみ焼却炉ボイラ内における高温腐食が問題となる中、耐高温腐食材料の開発が必要不可欠となっている。そこで、Ni基自溶合金溶射材に対して、皮膜の特性を改善する目的でガス及びレーザフュージングを施し、溶射まま材との比較を行うことで、これらの溶融処理が皮膜に及ぼす影響について検討した。

DOI： 10.14920/jwstaikai.2005s.0.31.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110004540983

記述言語：英語   掲載種別：研究論文（学術雑誌）

Spot welding is extensively used for joining aluminium alloys, although it is necessary to have available a large-capacity power source with a maximum capacity of around 300 000 A for joining by resistance seam welding 1 , low-current applications not being very often encountered. Recently developed welders, however, allow welding to proceed with ease at low currents of 20 or so kA. Joining of 1050/5052 by resistance seam welding was therefore tried together with a materials evaluation of joints. © 2005 Taylor and Francis Group, LLC.

DOI： 10.1533/wint.2005.3400

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

本研究では厚さ1.9mmのSPCC上において抵抗クラッディング法によって形成した超硬合金クラッド層のミクロ組織に関して検討を行った．この溶接条件は溶接電流2.7kA，溶接速度1.0m/min及び電極加圧力196Nである．

DOI： 10.14920/jwstaikai.2005f.0.208.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/130004641154

記述言語：英語   掲載種別：研究論文（学術雑誌）

Factors which influence magnetic leakage flux density due to a flaw in magnetic leakage flux testing are the shape and dimensions of the flaw, the B-H curves, the magnetizing conditions, lift-off, etc. The influence of B-H curves which were approximated by two lines was already reported and it was documented that both initial permeability and the magnetic flux density in the saturation state are the influence parameters. In the study we discuss here, we will document that the phenomenon of magnetic saturation - observed near the bottom of the flaw - is an essential effect when we concentrate on the influences of two parameters, i.e. the average magnetic flux density in a specimen and the intensity of magnetic field, both producing changes of the magnetic leakage flux density by using B-H curves modeled according to a two lines approach. © 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ndteint.2004.04.001

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

京都   2004年11月25日  -  2004年11月25日

主要論文集（会議）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌 代表的研究業績

記述言語：英語   掲載種別：研究論文（学術雑誌）

Titanium, a metal with superior sea water corrosion resistance, is increasingly used in titanium clad steel applications for ocean structures. Titanium clad steel is normally manufactured by hot rolling or explosive deposition. Joining of titanium and iron leads to the formation of hard and brittle intermetallic compounds that impair the bond strength. It is therefore necessary to use an insert metal to suppress the occurrence of these compounds, particularly during rolling. © 2004 Taylor and Francis Group, LLC.

DOI： 10.1533/wint.2004.3320

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

We performed ultrasonic bonding on sheets of 1050 and 5052 with different oxide thickness of 4, 15 and 30 μm. The oxide films macroscopically bent and distributed like whirl-shaped near bond interfaces. Microscopically, we observed two kinds of features of the oxide films, dot-shaped and line-shaped. We evaluated the bonding situation by an immersion method of ultrasonic testing (C-scope mode). The ratio of good bond area was ultrasonically obtained and depended on the thickness of the oxide films and input energy in bonding. The maximum tensile shear load decreased with the increase in the thickness of the oxide films. By using the results of both a tensile shear test and the good bond area obtained ultrasonically we could estimate the tensile shear strength of bonds.

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

We tried to bond A1050/A5052 and A1050/Cu by ultrasonic spot bonding and evaluated the bondability of joints by performing tensile shear test, the observation of microstructures and ultrasonic testing. In principle a good joint was obtained by ultrasonic bonding when we selected good bonding conditions and no intermetallic compound was observed at bond interface. It was observed that a crack initiated just before the maximum load near the boundary of the bond area of A1050 in both cases of A1050/ A5052 and A1050/Cu by radiographic testing during shear test. Then bond area started to deform and changed its shape from circle to ellipse and the crack propagated further. The maximum load in shear test was obtained at the appropriate input energy depending on the cases of A1050/A5052 and A1050/Cu. The situation of bonds could be evaluated by ultrasonic testing. We could observe nano-crystals near the bond interface of A1050/Cu with TEM probably due to the rapid deformation during the bonding.

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

2004年07月  -  2004年07月

主要論文集（会議）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌 代表的研究業績

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌 代表的研究業績

記述言語：英語   掲載種別：研究論文（学術雑誌）

Clad materials consisting of aluminum and aluminum plates were produced using the vacuum roll bonding method. This method produces an excellent bond without the intermetallic phase formation observable with conventional optical microscope. Bond interfacial structures in the AI/Ti clad material were observed by TEM, and the bonding mechanism were discussed. Tensile fracture occurred in the aluminum base metal of the clad material on the tensile test and the maximum tensile strength was 95 MPa. In addition, no cracks near the bonded zone were observed in the tensile fractured specimen. Nano-crystals and ultra fine-crystals were observed within the bonded zone using TEM. Within the ultra fine-crystal zone, the compositions of Al and Ti were approximately 30 and 20 at%, respectively. Precipitates those identified as a super lattice structure of the L12type and an intermetallic phase TiAl3(D0zztype), which are nano-meter size particles, were observed within the ultra fine-crystal zone having Al solid solution (FCC crystal) supersatulated with Ti. The bonding mechanism of aluminum to titanium on the vacuum roll bonding method can be considered that very small thin regions of aluminum surface to be bonded are melted by frictional heat due to the great relative sliding between aluminum and titanium plates during the roll bonding. After that the bonded zone is cooled rapidly due to the diffusion of the heat from the bonded zone toward each base metal and rolls, therefore, the nano-crystals and the ultra fine-crystals are formed in the bonded zone.

DOI： 10.2207/qjjws.22.254

Scopus

CiNii Article

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

廃棄物焼却炉のボイラチューブでは付着灰中に含まれる低融点塩化物などにより激しい腐食を生じることがしられている。そこで、本研究では溶射皮膜にレーザ照射を施し、高機能化の可能性を検討した。

DOI： 10.14920/jwstaikai.2004s.0.9.0

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003430838

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10012902139

記述言語：日本語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：英語   掲載種別：研究論文（学術雑誌）

We tried to bond A1050/A5052 and A1050/Cu by ultrasonic spot bonding and evaluated the bondability of joints by performing tensile shear test, the observation of microstructures and ultrasonic testing. In principle a good joint was obtained by ultrasonic bonding when we selected good bonding conditions and no intermetallic compound was observed at bond interface. It was observed that a crack initiated just before the maximum load near the boundary of the bond area of A1050 in both cases of A1050/A5052 and A1050/Cu by radiographic testing during shear test. Then bond area started to deform and changed its shape from circle to ellipse and the crack propagated further. The maximum load in shear test was obtained at the appropriate input energy depending on the cases of A1050/A5052 and A1050/Cu. The situation of bonds could be evaluated by ultrasonic testing. We could observe nano-crystals near the bond interface of A1050/Cu with TEM probably due to the rapid deformation during the bonding.

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

The yoke-magnetization is very popular in magnetic particle testing of welds. The detectability of a flaw by using this method largely depends on the magnetic flux density passing through a specimen to be examined or on the intensity of magnetic field acting in/on the specimen. In Japan inspectors have to check and confirm the appropriate magnetizing situation of the specimen by using an A-type standard test specimen specified in the standard JIS G 0565-1992. The development of indications by magnetic particles on the standard specimen is influenced by the air gap between the standard specimen and the specimen surface to be examined. Since the height and breadth of an artificial flaw in the standard specimen also influence the leakage of the magnetic flux density from the flaw, the information about the magnetizing situation is complex. In this paper we first identify influences of some factors on the magnetic leakage flux density from an artificial flaw in the standard specimen by using FEM modeling. Since the check with the standard specimen gives not a unique information to the magnetization state we investigate the technique, in which intensity of magnetic field acting on the specimen surface is used to characterize the magnetization. A finite element approach is applied to model the magnetization situation. The effectiveness of the modeling is confirmed by an experiment. © 2003 Elsevier Ltd. All rights reserved.

DOI： 10.1016/S0963-8695(03)00051-3

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌 代表的研究業績

記述言語：英語   掲載種別：研究論文（学術雑誌）

主要雑誌

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003430556

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003430537

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003433717

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003433718

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003433555

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）

記述言語：英語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

2002年04月  -  2002年04月

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）

2002年04月  -  2002年04月

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10007812963

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（学術雑誌）

Influences of chemical compositions of base metal, temperature difference Δ T between liquidus and solidus, and arc time on the susceptibility of liquation cracking were studied using the Varestraint test on 6082 aluminum alloy which was GTA spot welded. A commercial 6082 alloy and seven kinds of experimental 6082 alloy whose magnesium, silicon and manganese contents were changed were used. The susceptibility of liquation cracking was evaluated from the maximum crack length observed in heat affected zone after the Varestraint test. Liquation cracking was observed along grain boudaries on which low melting point compounds (mainly Mg2Si) were melted. The maximum crack length increased with arc time and Δ T. The addition of Si and Mg which increased Δ T promoted the liquation cracking, whereas the Mn addition suppressed the cracking by grain refining.

DOI： 10.2464/jilm.52.76

Scopus

CiNii Article

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記述言語：英語   掲載種別：研究論文（学術雑誌）

When applying nondestructive tests to evaluate the soundness of welded joints it is necessary to know the mechanical properties of the joints by destructive tests. In this paper it was tried to obtain the correlation between the data by the ultrasonic C-scope method and the absorbed energy by Charpy impact testing for diffusion bonded steel bars. The surface roughness of specimens (materials: 525C, mild steel) used for diffusion bonding was changed into several steps by machining and diffusion bonding was performed on five kinds of combinations of surface roughness. This process produced diffusion bonds whose ratio of non-bonded area was different. Ultrasonic testing was made using a frequency of 10 MHz and a 12.7 mm-diameter transducer. The ratio of non-bonded area was obtained by using C- scope method by immersion testing, and this depended on the threshold echo level when binarizing the images of C- scope presentation and the roughness of the specimen surface. The lower the threshold echo level, the larger the ratio of non-bonded area. The absorbed energy depended on the ratio of non-bonded area. It is made clear that the proper threshold echo level should be selected for evaluating the soundness of diffusion bonds by ultrasonic testing. Moreover, when transition liquid phase diffusion bonding was performed on SD345 (deformed reinforcing steel bar) using an amorphous Ni foil as an insert metal, the absorbed energy also decreased with the increase in the ratio of flaw area obtained by ultrasonic testing, though no change in the tensile strength was observed.

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

In the weld metal of A5083 welded with high energy density such as electron beam and laser beam, the amount of solute (mainly magnesium) of the primary crystals tends to increase with the increase in the welding speed. The solute concentration of solid phase tends to increase generally with the increase in the solid fraction and increases rapidly near the last stage of solidification, that is, the dendrite boundary. Though the dissolved amount of magnesium in the weld metal estimated with X-ray diffraction technique becomes lower than that of the base metal, this tends to approach to that of the base metal after the weld metal was homogenized. In this paper, we examined these phenomena more precisely. First, we calculated the distributions of magnesium by applying the rapid solidificatio theory when the dendrite arm spacings (DAS) were changed to several steps. Then, the dissolved amount of magnesium in the dendrite was calculated by considering the distributions of magnesium and we made clear the influence of DAS on the dissolved amount of magnesium. Next, we also calculated the distributions of magnesium when the weld metal was homogenized and made clear the influence of DAS on the dissolved amount of magnesium after the homogenization. Moreover, the actual weld metals, in which DAS were changed, were obtained by changing the welding conditions with electron beam and we could experimentally confirm the same tendency as mentioned above which were simulated by the calculation. It was made clear that the Charpy impact energy of the weld metals linearly increased with the increase in the dissolved amount of magnesium.

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003422131

記述言語：日本語   掲載種別：研究論文（学術雑誌）

代表的研究業績

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

In the weld metal of A5083 welded with high energy density such as electron beam and laser beam, the amount of solute (mainly magnesium) of the primary crystals tends to increase with the increase in the welding speed. The solute concentration of solid phase tends to increase generally with the increase in the solid fraction and increases rapidly near the last stage of solidification, that is, the dendrite boundary. Though the dissolved amount of magnesium in the weld metal estimated with X-ray diffraction technique becomes lower than that of the base metal, this tends to approach to that of the base metal after the weld metal was homogenized. In this paper, we examined these phenomena more precisely. First, we calculated the distributions of magnesium by applying the rapid solidification theory when the dendrite arm spacings (DAS) were changed to several steps. Then, the dissolved amount of magnesium in the dendrite was calculated by considering the distributions of magnesium and we made clear the influence of DAS on the dissolved amount of magnesium. Next, we also calculated the distributions of magnesium when the weld metal was homogenized and made clear the influence of DAS on the dissolved amount of magnesium after the homogenization. Moreover, the actual weld metals, in which DAS were changed, were obtained by changing the welding conditions with electron beam and we could experimentally confirm the same tendency as mentioned above which were simulated by the calculation. It was made clear that the Charpy impact energy of the weld metals linearly increased with the increase in the dissolved amount of magnesium.

DOI： 10.2207/qjjws.19.656

Scopus

CiNii Article

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0035520773&origin=inward

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10007535825

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10007535538

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10007535540

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10007535539

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10007535746

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003430239

記述言語：英語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

代表的研究業績

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1080/09507110109549398

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85011188901&origin=inward

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1080/09507110109549457

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）

The yoke method is usually used for magnetic particle testing of welds. In this paper, the influence of the air gap between a magnetic pole and the specimen surface on the average magnetic flux density passing through the specimen and the specimen thickness on leakage magnetic flux density from a flaw using the finite element method (FEM) is studied. When the air gap increases, the average magnetic flux density at the center of the specimen length decreases. The intensity of the magnetic field on the specimen surface can be estimated by extrapolating the magnetic flux density in space to that at lift-off being zero. Moreover, the maximum leakage magnetic flux density from a flaw decreases with the increase in the specimen thickness even if the average magnetic flux density passing through the specimen is the same.

Scopus

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

We investigate the development and the growth feature of columnar crystals in weld metals near the fusion boundary in 99.99% Al, A1050 and A5052 welded using laser. In the case of 99.99% Al, the columnar crystals which are developed epitaxially grow toward the center of the weld metals when shielded in argon. However, stray crystals are often observed in the weld metals shielded in nitrogen gas. This results from the development of cell structure and the competitive growth tends to occur due to the absorption of the trace of nitrogen gas in Al. The weld metals shielded in nitrogen gas are harder than the weld metals shielded in argon. This is caused by the development of AlN. The development of the stray crystals becomes easier in A5052 than in A1050. In the case of A5052, it is very rare that epitaxial growth is clearly recognized and many stray crystals begin to grow from very near the fusion boundary. The growth rate of the columnar crystals increases as welding speed increases. The growth rate of columnar crystals when welded with pulse laser is faster than that welded with continuous laser. The maximum value obtained is 1.9 m/min and this is faster than that obtained in the weld metal welded by GTA.

Scopus

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記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10004667628

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10022559207

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003431785

記述言語：日本語   掲載種別：研究論文（学術雑誌）

代表的研究業績

記述言語：英語   掲載種別：研究論文（学術雑誌）

The yoke method is usually used as a magnetic testing method of welds. In this paper, we study the influences of the air gap between the magnetic pole and the specimen surface on the average magnetic flux density passing through the specimen, and the specimen thickness on the leakage magnetic flux density from a flaw using finite element method (FEM). When the air gap increases the average magnetic flux density at the center of the specimen length decreases. We can estimate the intensity of the magnetic field on the specimen surface by extrapolating the magnetic flux density in space to that at lift-off being zero. Moreover, the maximum leakage magnetic flux density from a flaw decreases with increase in the specimen thickness even if the average magnetic flux density passing through the specimen is the same.

DOI： 10.1016/S0963-8695(99)00060-2

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0033893094&origin=inward

記述言語：英語   掲載種別：研究論文（学術雑誌）

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）

2000年04月  -  2000年04月

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）

2000年04月  -  2000年04月

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10004813366

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003429505

記述言語：英語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）

DOI： 10.1080/09507119909447435

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85011124246&origin=inward

記述言語：英語   掲載種別：研究論文（学術雑誌）

代表的研究業績

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003429382

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003429335

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）

1998年04月  -  1998年04月

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003494976

記述言語：英語   掲載種別：研究論文（学術雑誌）

The macroscopic solidification structures developed in the weld metal of aluminium alloys are generally columnar crystals and equiaxed dendrites. The development of these macrostructures depends on the welding conditions. Feathery crystals are sometimes developed during low-speed GTA (TIG) welding. This paper describes an investigation of the characteristics of feathery crystals by scanning acoustic microscopy (SAM) and transmission electron microscopy (TEM). SAM enables structures to be observed without etching. The growth features of feathery crystals are clarified by observations made normal and parallel to the welding direction. Measurements of the velocity of the elastic surface wave of feathery crystals by SAM with an anisotropic acoustic lens show the velocity to be around 100 m/sec faster parallel to the welding direction than normal to it, confirming that the feathery crystals are acoustically anisotropic. Feathery crystals are also observed in electron beam welds by SAM, although it is not generally easy to observe the macrostructures of these welds because of the beam width being narrow. The diffraction patterns and TEM observations of the feathery crystals show them to be twinned crystals with the (111) plane as their twinning plane. © 1997 Taylor and Francis Group, LLC.

DOI： 10.1080/09507119709448446

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85009577195&origin=inward

記述言語：日本語   掲載種別：研究論文（学術雑誌）

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10002581136

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/10002581293

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003428807

記述言語：日本語   掲載種別：研究論文（学術雑誌）

CiNii Article

その他リンク： https://ci.nii.ac.jp/naid/110003428567

記述言語：英語   掲載種別：研究論文（学術雑誌）

Microcracks developed in the cleaning action region during the GTA (TIG) process have been investigated using aluminium and aluminium alloys. Although no microcracks are found in pure aluminium and commercially pure aluminium, microcracks are mainly developed in Al‐Mg alloys where the oxide film is ruptured by the cleaning action. The microcracking trend found is analogous to the weld solidification crack susceptibility of Al‐Mg alloys, and the microcracks developed in the cleaning action region are predicted to be related to solidification cracks. The microcracks readily develop with an increasing EN ratio of the welding current. A pattern of solidified dendrites is clearly visible, suggesting that the microcracking has developed by the cathode spot formed leading to local melting. The microcracking is also intergranular. The cooling rate during solidification can be estimated from the dendrite size, being put at around 104°C/sec. Microcrack development is considered to be due to the fact that the region where the oxide film is ruptured is locally melted by the high current density and the very high cooling rate. The X‐ray diffraction results suggest that continuous faint Debye‐Scherrer rings are obtained from the region where the oxide film is ruptured even when a single crystal is used. The single crystal here changes to very small polycrystals in this region, the polycrystallised depth from the specimen surface being around 100 μm. The fatigue strength of microcracked specimens at 1 × 107cycles is lower than that of the base metal, decreasing linearly with an increasing crack’ depth. © 1995 Woodhead Publishing Ltd.

DOI： 10.1080/09507119509548814

Scopus

その他リンク： https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84952233035&origin=inward

記述言語：日本語   掲載種別：研究論文（学術雑誌）

開催期間： 2019年11月21日 - 2019年11月22日   記述言語：英語   開催地：ホテル阪急エキスポパーク  

開催期間： 2019年11月21日 - 2019年11月22日   記述言語：英語   開催地：ホテル阪急エキスポパーク  

開催期間： 2019年11月12日 - 2019年11月15日   記述言語：英語   開催地：東京大学　伊藤謝恩ホール  

開催期間： 2019年11月12日 - 2019年11月15日   記述言語：英語   開催地：東京大学　伊藤謝恩ホール  

開催期間： 2019年11月01日 - 2019年11月03日   記述言語：日本語   開催地：東京農工大学　小金井キャンパス  

開催期間： 2019年11月01日 - 2019年11月03日   記述言語：日本語   開催地：東京農工大学　小金井キャンパス  

開催期間： 2019年11月01日 - 2019年11月03日   記述言語：日本語   開催地：東京農工大学　小金井キャンパス  

開催期間： 2019年11月01日 - 2019年11月03日   記述言語：日本語   開催地：東京農工大学　小金井キャンパス  

開催期間： 2019年09月17日 - 2019年09月19日   記述言語：日本語   開催地：東北大学　工学部　材料科学総合学科  

開催期間： 2019年09月17日 - 2019年09月19日   記述言語：日本語   開催地：東北大学　工学部　材料科学総合学科  

開催期間： 2019年09月11日 - 2019年09月13日   記述言語：日本語   開催地：岡山大学津島キャンパス  

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開催期間： 2019年06月12日   記述言語：日本語   開催地：溶接会館会議室  

開催期間： 2018年11月09日 - 2018年11月11日   記述言語：日本語   開催地：芝浦工業大学豊洲キャンパス  

開催期間： 2018年11月09日 - 2018年11月11日   記述言語：日本語   開催地：芝浦工業大学豊洲キャンパス  

開催期間： 2018年11月09日 - 2018年11月11日   記述言語：日本語   開催地：芝浦工業大学豊洲キャンパス  

開催期間： 2018年11月09日 - 2018年11月11日   記述言語：日本語   開催地：芝浦工業大学豊洲キャンパス  

開催期間： 2018年09月19日 - 2018年09月21日   記述言語：日本語   開催地：東北大学川内北キャンパス  

開催期間： 2018年09月19日 - 2018年09月21日   記述言語：日本語   開催地：東北大学川内北キャンパス  

開催期間： 2018年06月23日   記述言語：日本語   開催地：北九州国際会議場  

開催期間： 2018年06月23日   記述言語：日本語   開催地：北九州国際会議場  

開催期間： 2018年06月23日   記述言語：英語   開催地：北九州国際会議場  

開催期間： 2018年06月23日   記述言語：日本語   開催地：北九州国際会議場  

開催期間： 2018年03月19日 - 2018年03月21日   記述言語：日本語   開催地：千葉工業大学  

開催期間： 2017年12月12日   記述言語：日本語   開催地：九州工業大学　戸畑キャンパス  

開催期間： 2017年12月12日   記述言語：日本語   開催地：九州工業大学　戸畑キャンパス  

開催期間： 2017年12月07日 - 2017年12月08日   記述言語：日本語   開催地：くまもと県民交流館パレア  

開催期間： 2017年11月06日 - 2017年11月07日   記述言語：日本語   開催地：東京工業大学  

開催期間： 2017年11月04日 - 2017年11月05日   記述言語：日本語   開催地：宇都宮大学  

開催期間： 2017年09月19日 - 2017年09月21日   記述言語：日本語   開催地：蒲郡  

学生ポスターセッション　努力賞

開催期間： 2017年09月11日 - 2017年09月13日   記述言語：日本語   開催地：九州工業大学　戸畑キャンパス  

開催期間： 2017年09月11日 - 2017年09月13日   記述言語：日本語   開催地：九州工業大学　戸畑キャンパス  

開催期間： 2017年09月06日 - 2017年09月08日   記述言語：日本語   開催地：北海道大学  

学生ポスターセッション　努力賞

開催期間： 2017年06月22日   記述言語：日本語   開催地：九州国際会議場  

開催期間： 2017年06月22日   記述言語：日本語   開催地：九州国際会議場  

開催期間： 2017年03月15日 - 2017年03月17日   記述言語：日本語   開催地：首都大学東京  

開催期間： 2017年03月15日 - 2017年03月17日   記述言語：日本語   開催地：首都大学東京  

学生ポスターセッション　努力賞

開催期間： 2017年03月15日 - 2017年03月17日   記述言語：日本語   開催地：首都大学東京  

開催期間： 2016年12月17日 - 2016年12月18日   記述言語：英語   開催地：九州工業大学  

開催期間： 2016年12月17日 - 2016年12月18日   記述言語：英語   開催地：九州工業大学  

開催期間： 2016年12月02日   記述言語：日本語   開催地：九州工業大学  

開催期間： 2016年12月02日   記述言語：日本語   開催地：九州工業大学  

開催期間： 2016年11月05日 - 2016年11月06日   記述言語：日本語   開催地：茨城大学  

開催期間： 2016年10月11日 - 2016年10月14日   記述言語：英語   開催地：学術総合センター　一ツ橋ホール  

開催期間： 2016年10月11日 - 2016年10月14日   記述言語：英語   開催地：学術総合センター　一ツ橋ホール  

開催期間： 2016年10月11日 - 2016年10月14日   記述言語：英語   開催地：Albufeira, Algarve, Portugal,  

開催期間： 2016年10月06日 - 2016年10月07日   記述言語：英語   開催地：University of Stuttgart, Stuttgart, Germany  

開催期間： 2016年09月21日 - 2016年09月23日   記述言語：日本語   開催地：大阪大学  

開催期間： 2016年09月21日 - 2016年09月23日   記述言語：日本語   開催地：大阪大学  

学生ポスターセッション　努力賞

開催期間： 2016年09月14日 - 2016年09月16日   記述言語：日本語   開催地：群馬県・伊香保温泉　HOTEL 天坊  

開催期間： 2016年09月14日 - 2016年09月16日   記述言語：日本語   開催地：群馬県・伊香保温泉　HOTEL 天坊  

開催期間： 2016年08月29日 - 2016年08月31日   記述言語：日本語   開催地：箱根  

開催期間： 2016年08月29日 - 2016年08月31日   記述言語：日本語   開催地：箱根  

開催期間： 2016年07月17日 - 2016年07月24日   記述言語：英語   開催地：Vancouver, British Columbia, Canada  

開催期間： 2016年07月09日   記述言語：日本語   開催地：国立大学法人九州工業大学　百周年中村記念館　多目的ホール  

開催期間： 2016年07月09日   記述言語：日本語   開催地：国立大学法人九州工業大学　百周年中村記念館　多目的ホール  

開催期間： 2016年06月11日   記述言語：日本語   開催地：九州大学　筑紫キャンパス  

開催期間： 2016年06月11日   記述言語：日本語   開催地：九州大学　筑紫キャンパス  

開催期間： 2016年04月20日 - 2016年04月22日   記述言語：英語   開催地：Wuhan, China  

開催期間： 2016年04月12日 - 2016年04月14日   記述言語：日本語   開催地：ATC（アジア太平洋トレードセンター） O's 南6 階（コンベンションルーム1，2，B7，B8会議室）  

開催期間： 2015年09月16日 - 2015年09月18日   記述言語：日本語   開催地：九州大学  

開催期間： 2015年09月16日 - 2015年09月18日   記述言語：日本語   開催地：九州大学  

開催期間： 2015年09月02日 - 2015年09月04日   記述言語：日本語   開催地：北海道科学大学  

開催期間： 2015年09月02日 - 2015年09月04日   記述言語：日本語   開催地：北海道科学大学