鋼/アルミニウムの固相接合に鋼種が与える影響

―鍛造異材固相接合の研究　第2報―

抄録

In this research, the effect of steel grade on the solid-phase forge welding (SPFW) of steel/Al was investigated. In a previous study, a new test method for evaluating SPFW was developed. Using this method, we prepared test pieces bonded with SUS304/A1070 by varying the surface enlarging ratio ( Π _Steel ) and surface pressure ( P ) at the interface. After bonding, tension tests were performed to measure bonding strength. In this research, the same experiments were performed using S10C/A1070. It was found that strong bonding was obtained above Π _Steel = 3.5 and P = 990 MPa in S10C/A1070. However, the bonding strength measured using the test pieces bonded with S10C/A1070 showed a larger scatter than in the case of using SUS304/A1070 ones. After the tensile tests, the fracture surfaces (for SUS304/A1070 and S10C/A1070) were observed by electron microscope. It was confirmed that the oxide films were broken following with the surface enlarging in both metal combinations. After the surface enlargement, intact virgin areas were allowed to come into contact with each other and bonded. In addition, it was confirmed that the areas of the oxide film and aluminum lump adhesion in S10C/A1070 were clearly smaller than those SUS304/A1070.