Development of high performance laminate type hydrogen storage alloys by using extreme severe plastic deformation (ESPD) and hydrogenation disproportionation desorption recombination (HDDR)

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K06519
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Material processing/Microstructural control engineering
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Tanaka Koji 国立研究開発法人産業技術総合研究所, エネルギー・環境領域, 主任研究員 (40357439)
• Co-Investigator(Kenkyū-buntansha): 竹下 博之 関西大学, 化学生命工学部, 教授 (20351497) ; 近藤 亮太 関西大学, 化学生命工学部, 助教 (60709088)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 積層型 / 水素吸蔵合金 / 極強加工 / 水素誘起分解再結合 / 低温合金化 / 合金化速度 / 競合反応 / 微細組織

Outline of Final Research Achievements

It is found that the growth rate constants of Mg2Cu in Mg/Cu super-laminate composites (SLCs) is approximately ten to the second - forth order larger than that of Mg-Cu diffusion couples. It is because that extreme severe plastic deformation such as accumulative roll bonding (ARB) with more than 5 cycles can enhance atomic diffusion and promote solid-state reactions because of an increase in the density of lattice defects such as vacancies, dislocations and grain boundaries. It is also found that hydrogenation of Mg was dominant in Mg/Cu SLCs during initial hydrogenation of Mg/Cu SLCs when Mg was thick, whereas that of Mg2Cu was dominant in Mg/Cu SLCs when Mg was thin. It is considered that the average thickness of Mg + Cu layers in as-rolled Mg/Cu SLCs as a function of ARB cycles has a large influence on initial hydrogenation properties and microstructure formation processes.

Free Research Field

材料工学