Mechanical Properties of Weld Bonded Joint in New Dissimilar Metal Joining Method Using Refill Friction Stir Spot Welding

Abstract

　Friction stir spot welding (FSSW) is one of the solid state welding methods, and it is getting attention as a dissimilar metal joining method. We have developed a new dissimilar material joining method —scrubbing refill FSSW (Sc-RFSSW)—, and this new method is based on the concept of rapid formation of a newly formed surface by the interaction of high-hardness tool with the surface of lower plate. In this study, weld bonding with Sc-RFSSW was performed and joint strength and adhesive discharge process were analyzed. In the strength evaluation, it was suggested that the Sc-RFSSW spot strength did not decrease even if the adhesive was placed between the upper plate and lower plate, and the sufficient strength per welded area was obtained in the Sc-RFSSW joint. In addition, it was shown that the adhesive was sufficiently discharged from the interface.