Development of high strength nanocrystalline alloys with high ductility controlled by dynamic structural changes during plastic deformation

2016 Fiscal Year Final Research Report

• Project/Area Number: 25249103
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Material processing/Microstructural control engineering
• Research Institution: University of Hyogo
• Principal Investigator: Yamasaki Tohru 兵庫県立大学, 工学研究科, 教授 (30137252)
• Co-Investigator(Kenkyū-buntansha): 足立 大樹 兵庫県立大学, 工学(系)研究科(研究院), 准教授 (00335192) ; 藤田 和孝 宇部工業高等専門学校, その他部局等, 教授 (10156862) ; 網谷 健児 東北大学, 金属材料研究所, 准教授 (30463798) ; 三浦 永理 兵庫県立大学, 工学(系)研究科(研究院), 准教授 (70315258) ; 早乙女 康典 東北大学, 金属材料研究所, 教授 (90143198)
• Project Period (FY): 2013-10-21 – 2017-03-31
• Keywords: 電解析出 / Ni-W合金 / ナノ結晶 / アモルファス / 加工硬化 / 放射光 / マイクロビーム

Outline of Final Research Achievements

Nanocrystalline and amorhpous bulk metallic alloys have been limited in practical applications because of their low ductility under tensile and compressive testing conditions. This may be due to the formation of highly localized shear bands during plastic deformation. We have developed the high strength Ni-W electrodeposited alloys having large plastic deformability during tensile tests, e.g., tensile strength of about 2000 - 3000 MPa with plastic strain abour 1% - 7%. This may be due to the dynamic nanocrystalline grain growth during plastic deformation. In addition, small amounts of Au addition on the Zr-Cu-Ni-Al BMGs have accelerated dynamic precipitations of nano-scale icosahedral quasicrystal phase (I-phase) inside the shear bands　during plastic deformation. As the results, crystallization behaviors of the I-phase during plastic deformation have large remedial effects on the　mechanical properties of the Zr based BMGs

Free Research Field

材料設計学