Abstract
Friction stir welding (FSW) by using the self-reacting tool offers a solution to conventional FSW problem by using the fixed tool. Self-reacting tool is composed of upper and lower shoulder. To weld distorted material without inner pores, controlled pinch force between upper and lower shoulder succeeded in self-reacting FSW. The optimum welding condition of self-reacting tool was not wider than that of fixed-tool. Mechanical property of weld section by using the self-reacting tool was as strong as by fixed tool.
