Grant-in-Aid for Scientific Research (A).
|Research Institution||TOHOKU UNIVERSITY|
ISHIDA Kiyohito NICHe, Tohoku University, Professor, 未来科学技術共同研究センター, 教授 (20151368)
小林 和雄 株式会社 富士通研究所, ペリフェラルシステム研究所, 主管研究員
星 俊治 ヤマハ株式会社, 研究開発本部・材料研究所, 副所長(研究職)
鈴木 雄一 古河電工株式会社, 横浜研究所, 所長(研究職)
OHNUMA Ikuo Graduate School of Engineering, Tohoku University, Research Associate, 大学院・工学研究科, 助手 (20250714)
KAINUMA Ryosuke Graduate School of Engineering, Tohoku University, Associate Professor, 大学院・工学研究科, 助教授 (20202004)
SUZUKI Yuichi Yokohama Research Center, Furukawa Electronic Ltd., Manager of the Center
KOBAYASHI Kazuo Peripheral System Research Center Department, Fujitsu Research Center Ltd., Senior Researcher
HOSHI Toshiharu R & D Center for materials, Yamaha Ltd., Vice-manager of the Center
|Project Fiscal Year
1997 – 1999
Completed(Fiscal Year 1999)
|Budget Amount *help
¥30,200,000 (Direct Cost : ¥30,200,000)
Fiscal Year 1999 : ¥8,500,000 (Direct Cost : ¥8,500,000)
Fiscal Year 1998 : ¥8,200,000 (Direct Cost : ¥8,200,000)
Fiscal Year 1997 : ¥13,500,000 (Direct Cost : ¥13,500,000)
|Keywords||High Strength Alloys / Shape Memory Alloys / GMR Materials / Phase Separation / Order-disorder Transition / Cu-Mn-Al Alloys / Heusler Alloys / Cu-Al Base Alloys / 高強度合金 / 形状記憶合金 / 巨大磁気抵抗材料 / 2相分離 / 規則-不規則変態 / Cu-Mn-Al合金 / ホイスラー合金 / Cu-Al基合金 / 巨大磁気記録材料 / ホイスラ-合金|
It is known that there are many kinds of transformations, such as A2/B2/D03/L21 order-disorder transitions, magnetic transition and phase separation in their ordered phases, in the β phase of the Cu-Al-Mn alloys. The purpose of this study is to develop some new types of Cu base alloys using these transformations. Actually high strength Cu alloys, shape memory (SM) alloys and giant magnetoresistance (GMR) thin films were examined in the present study. All the results obtained in this study are listed as follows :
(1) High Strength Cu Alloys :
In the Cu-13%Al-15%Mn-5%Ni alloys, very high level of tensile strength over 1000MPa were achieved due to aging at 300℃. According to TEM observation, it is seen that the microstructure of the as-aged specimens has a kind of bainate structure with very fine scale. Since such the high level of strength in the Cu base alloys has not been reported except the Cu-Be alloys, the present alloys have a potential for a new kind of high strength Cu base alloys.
(2) Shape Memory Alloys
Effects of alloying elements on the fabricability, Ms temperature and SM properties were examined. It was clarified that the precipitates decrease ductility, Si, Au and Co increase the Ms temperature and the SM properties are strongly influenced by grain size and texture.
(3) Giant Magnetoresistance Thin Films
GMR properties of Cu-Al-Mn alloys with wide range of compositions were examined. It was clarified that the Cu-25%Al-10%Mn alloy which has the volume fraction of Cu2MnAl:Cu3Al=3:7 shows the highest GMR ratio over 4%.
Based on the above results, joint projects for practical applications with some companies are running.