While letting flow

摘要

PPROBLEM TO BE SOLVED: To provide a joining method by which the occurrence of blow holes at the welded part is suppressed when a welded part formed by friction stir welding is thereafter subjected to fusion welding. PSOLUTION: The members A, B to be welded are subjected to friction stir welding as an inert shielding gas is made to flow to thereby form a welded part C. Thereafter, the welded part is subjected to fusion welding. Alternatively, the members to be welded are subjected to friction stir welding to thereby form a welded part, and thereafter, the welded part is subjected to fusion welding as ultrasonic waves are applied thereto. Further, the members to be welded are subjected to friction stir welding while an inert shielding gas is made to flow to thereby form a welded part. Then, the welded part is subjected to fusion welding as ultrasonic waves are applied thereto. The regulation of the frequency of the ultrasonic waves to 1 to 30 kHz is effective for suppressing the occurrence of blow holes. PCOPYRIGHT: (C)2007,JPO&INPIT