C. D. Allen, South Dakota School of Mines & Technology, Rapid City, SD
Summary: The Friction Spot Welding (FSSW) process as invented by GKSS in Germany has shown potential for application in several industrial fields as a solid state joining technology in alloys that are not easily weldable by conventional means. This FSSW process is characterized by a high degree of refill which results in a nearly flush weld surface. The static and fatigue strengths of friction spot welds in lap-shear specimens of 7075-T6 aluminum in a two stack joint are presented. The effects of processing parameters on the mechanical and metallugical responses are quantified and the results are compared to riveting and resistance spot welding. The results show that the FSSW process is capable of producing good quality welds with moderate cycle times and process forces that compare favorably to resistance spot welding.