研究者詳細 - 山口　富子

論文 - 山口　富子

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Formation and Friction Properties of Electron Beam Cladding (Ti, W)C<inf>1-x</inf> Composite Coatings on Ti-6Al-4V 査読有り国際誌

Liu D., Chen Q., Wang D., Zhang R., Tomiko Y., Wang W.

Jinshu Xuebao/Acta Metallurgica Sinica 56 ( 7 ) 1025 - 1035 2020年07月

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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Rapid fabrication of the continuous AlFeCrCoNi high entropy alloy coating on aluminum alloy by resistance seam welding 査読有り国際誌

Zhao D., Yamaguchi T., Shu J., Tokunaga T., Danjo T.

Applied Surface Science 517 2020年07月

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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Fabrication and wear performance of Al<inf>0.8</inf>FeCrCoNi high entropy alloy coating on magnesium alloy by resistance seam welding 査読有り

Zhao D., Yamaguchi T., Wang W.

Materials Letters 265 2020年04月

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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Influence of a Ni Foil Interlayer on Interface Properties of Mg-Clad Al Materials by Vacuum Roll Bonding 査読有り国際誌

Shu Jinfeng, Yamaguchi Tomiko, Hara Yuya

MATERIALS TRANSACTIONS ( 公益社団法人日本金属学会 ) 61 ( 5 ) 1020 - 1025 2020年01月

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 Mg<sub>2</sub>Ni intermetallic compound with a 0.9 µm thickness on the Mg–Ni interface, which was smaller than that of the intermetallic compounds (Al<sub>12</sub>Mg<sub>17</sub> of 1.77 µm and Al<sub>3</sub>Mg<sub>2</sub> 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 Mg<sub>2</sub>Ni intermetallic compound on the Mg–Ni interface after heat treatment were investigated. The growth activation energy of Mg<sub>2</sub>Ni was 157.24 kJ/mol, which is higher than that of Al<sub>3</sub>Mg<sub>2</sub> which mainly affects the Al–Mg interfacial bonding strength. Therefore, the thickness of the Mg<sub>2</sub>Ni was thinner and the interfacial bonding strength was greater after the vacuum roll bonding.</p>

DOI： 10.2320/matertrans.MT-M2019277

その他リンク： https://ci.nii.ac.jp/naid/130007806209

Growth Characteristics of Intermetallic Compounds on the Bond Interface of Magnesium-Clad Aluminum and Its Effect on Interface Properties 査読有り

Shu Jinfeng, Yamaguchi Tomiko

軽金属溶接 ( 一般社団法人軽金属溶接協会 ) 58 ( 0 ) 107s - 112s 2020年01月

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 Al<sub>3</sub>Mg<sub>2</sub> layer with 2 μm thickness was observed after 3h. Al<sub>3</sub>Mg<sub>2</sub> and Al<sub>12</sub>Mg<sub>17</sub> intermetallic layers were formed at and above 300℃, and the growth activation energy of Al<sub>3</sub>Mg<sub>2</sub> (86.18 kJ/mol) is smaller than that of Al<sub>12</sub>Mg<sub>17</sub> (115.33 kJ/mol), so the growth of Al<sub>3</sub>Mg<sub>2</sub> 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 Al<sub>3</sub>Mg<sub>2</sub> layer, and the mode of fracture were cleavage fracture.</p>

DOI： 10.11283/jlwa.58.107s

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レーザ照射による低炭素鋼および鋳物の部分硬化技術の開発招待有り査読有り

山口富子, 毛利陽一, 北川義大

レーザ加工学会誌 ( 一般社団法人レーザ加工学会 ) 27 ( 3 ) 162 - 163 2020年01月

Fabrication and characterization of Pr6O11-HfO2 ultra-high temperature infrared radiation coating 査読有り

Liu, F., Cheng, X, Mao, J., Li, S., Shao, H., Liu, T., Yamaguchi, T., Zeng, X.

Journal of the European Ceramic Society 39 ( 14 ) 4208 - 4215 2019年11月

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

Fabrication and characterization of Pr<inf>6</inf>O<inf>11</inf>-HfO<inf>2</inf> ultra-high temperature infrared radiation coating 査読有り国際誌

Liu F., Cheng X., Mao J., Li S., Shao H., Liu T., Yamaguchi T., Zeng X.

Journal of the European Ceramic Society 39 ( 14 ) 4208 - 4215 2019年11月

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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Bond characteristics of Al/Mg clad materials produced by vacuum roll bonding 査読有り国際誌

Shu J., Yamaguchi T.

IOP Conference Series: Materials Science and Engineering 576 ( 1 ) 2019年08月

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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Hydrostatic pressure effects on superconducting transition of nanostructured niobium highly strained by high-pressure torsion 査読有り国際誌

Mito, M., Kitamura, Y., Tajiri, T., Nakamura, K., Shiraishi, R., Ogata, K., Deguchi, H., Yamaguchi, T., Takeshita, N., Nishizaki, T., Edalati, K., Horita, Z.

Journal of Applied Physics 125 ( 12 ) 2019年03月

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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Effect of creep degradation on hardness changes of Ni-based alloys for A-USC power boiler 査読有り国際誌

Saito N., Ishiyama K., Yamaguchi T., Masuyama F.

ISIJ International ( 一般社団法人日本鉄鋼協会 ) 59 ( 9 ) 1695 - 1704 2019年01月

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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HIGH TEMPERATURE OXIDATION BEHAVIOR OF HIGH NITROGEN FERRITIC STEELS 査読有り

Masuyama F., Matsubara S., Tonoe Y., Yamaguchi T.

Joint EPRI-123HiMAT International Conference on Advances in High-Temperature Materials - Proceedings from EPRI's 9th International Conference on Advances in Materials Technology for Fossil Power Plants and the 2nd International 123HiMAT Conference on High-Temperature Materials 282 - 293 2019年01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）

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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High temperature oxidation behavior of high nitrogen 9%cr steels 査読有り国際誌

Matsubara S., Yamaguchi T., Masuyama F.

ISIJ International ( 一般社団法人日本鉄鋼協会 ) 58 ( 11 ) 2095 - 2101 2018年11月

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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Effect of Cr content and microstructure on high temperature oxidation behavior of high nitrogen heat-resistant ferritic steels 査読有り国際誌

Matsubara S., Yamaguchi T., Masuyama F.

ISIJ International ( 一般社団法人日本鉄鋼協会 ) 58 ( 11 ) 2102 - 2109 2018年11月

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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Characteristics of surface modified Ti-6Al-4V alloy by a series of YAG laser irradiation 査読有り国際誌

Zeng X., Wang W., Yamaguchi T., Nishio K.

Optics and Laser Technology 98 106 - 112 2018年01月

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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Fabrication, microstructure, and wear performance of WC-Fe composite/metal coating fabricated by resistance seam welding 査読有り国際誌

Wang W., Zeng X., Li Y., De Wang, Liu Y., Yamaguchi T., Nishio K., Cao J.

Materials Characterization 134 182 - 193 2017年12月

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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抵抗クラッディング法によるアルミニウムクラッド材の開発

山口富子, 王文琴

フジコー技報　創る ( 株式会社　フジコー ) ( 25 ) 14 - 17 2017年12月

New ferritic steel beyond grade 92 and its creep degradation assessment by hardness method for grade 91 査読有り国際誌

Masuyama F., Yamaguchi T.

ASME 2014 Symposium on Elevated Temperature Application of Materials for Fossil, Nuclear, and Petrochemical Industries, ETAM 2014 2017年01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）

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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真空圧延接合法により作製したA1050/C1020クラッド材の接合部強さに及ぼす接合条件の影響査読有り

松本悟, 山口富子, 西尾一政

溶接学会全国大会講演概要 ( 一般社団法人溶接学会 ) 2017 ( 0 ) 314 - 315 2017年01月

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

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

YAGレーザ照射によるチタン上への硬質層の形成に関する研究査読有り

山口富子

天田財団助成研究成果報告書 ( 公益財団法人天田財団 ) 30 ( 0 ) 230 - 234 2017年01月

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