Development of simultaneous friction welding technique with low heat input for difficult materials combination with insert metal

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K03775
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18010:Mechanics of materials and materials-related
• Research Institution: University of Hyogo
• Principal Investigator: Kimura Masaaki 兵庫県立大学, 工学研究科, 准教授 (90285338)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 摩擦圧接 / A7075 / 軟鋼 / 純Ti / インサート材 / 同時接合 / マルチマテリアル

Outline of Final Research Achievements

The dissimilar joint with the material to difficult welding such as A7075-T6 aluminum alloy fabricated by friction welding is strongly required in the industry field. The purpose of this study is the development of the simultaneous friction welding method with low heat input for making the joint without the weld interface fracture. In this study, the materials combination was A7075-T6 and low carbon steel (S15CK) that was difficult to welding of the direct joining, and those materials were simultaneous friction welded through using an insert metal of pure Ti. Then, the characteristics of those joints, which had the various insert metal shapes as well as various friction welding conditions, were evaluated. Additionally, the guideline of friction welding condition was investigated to expand of the friction welding method with low heat input for a multi-material structure.

Free Research Field

溶接工学

Academic Significance and Societal Importance of the Research Achievements

継手は，軟鋼母材の降伏強さ超える高い引張強さが得られたため，純Tiのインサート材を介したA7075-T6と軟鋼との低入熱同時摩擦接合技術を示すとともに，接合条件の選定指針の目安を得ることができた．現状では軟鋼母材と同等の引張強さを有して軟鋼側から破断する良好な継手が得られていないが，引き続き検討を行うことでそれが実現できると考えている．それにより，これまで実現できなかった異種材料との組み合わせでも接合できる可能性があり，マルチマテリアル化に大きく貢献する．それは，我が国の国際競争力に打ち勝つものづくり産業の発展に繋がり，自動車産業のみならず各種産業分野に大きく波及するため，社会的意義も大きい．