FRICTION STIR WELDING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a friction stir welding method capable of overcoming the shortage of a metal in an inner corner in friction stir welding of the butting part from the inner corners of the metal components.SOLUTION: There is provided a friction stir welding method welding two metal components 10, 20 in which the shapes of faces to be butted are different from each other using a welding rotation tool F having an agitation pin F2. The method includes: a butting process of forming a butting part J1 by butting one metal component 10 and the other metal component 20; a build-up welding process of covering the inner corners of the metal components 10, 20 using a welding metal U by applying a build-up welding to the butting part J1 over a circumferential direction of the other metal component 20; and a welding process of performing the friction stir welding of the butting part J1 over the circumferential direction of the other metal component 20 in a state where a rotating agitation pin F2 is inserted in the inner corner and the agitation pin F2 only is contacted to the weld metal U and the metal components 10, 20.