High quality Fe / Al joining by in-situ synthesis of amorphous alloy bonding layer

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K14409
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Structural/Functional materials
• Research Institution: Chiba University
• Principal Investigator: Itoi Takaomi 千葉大学, 大学院工学研究院, 准教授 (50333670)
• Co-Investigator(Kenkyū-buntansha): 石橋 正基 東京都立産業技術高等専門学校, ものづくり工学科, 准教授 (40353263)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: 接合 / 電磁圧接 / 異種金属 / 接合界面

Outline of Final Research Achievements

Joint sheets of A1050-H24/SPCC(Ni) and A6061-T6/DP(Dual phase)590(Ni) were fabricated by magnetic pulse welding (MPW). Strong joints were achieved at discharge energy W of >1.0kJ and gap length d of 1.0 mm for the A1050-H24/SPCC(Ni), and W of 3.0kJ and d = 0.8 or 1.0 mm for the A6061-T6/DP590(Ni) steel, respectively. Weld interface showed wavy joint interface and an intermediate layer along the weld interface was recognized. Microstructure observations of the intermediate layer revealed that the Ni-coated region was consisted of an Ni-Al binary amorphous alloy, due to localized melting and a subsequent high rate cooling of molten Ni and Al confined to the weld interface. Since the Ni plating showed lower hardness than that of DP 590 steel, the amorphous phase is formed at the joint interface at a lower collision speed than the case where the Al alloy directly impacts the steel sheet, and then formed a high-quality bonding interface.

Free Research Field

材料工学