Friction stir welding method and friction stir welding member for aluminum alloy and steel plate

摘要

PPROBLEM TO BE SOLVED: To provide a friction stir welding method with which a weld joint of high joint strength is obtained by making a joint boundary greater in friction stir welding of different kinds of metallic materials, and to provide a friction stir welding member. PSOLUTION: In the friction stir welding method, in the friction stir welding of the different kinds of metallic materials, a low melting point plated steel sheet 30 as the metallic material of a high melting point has a plating layer 30a of the melting point lower than the melting point of an aluminum alloy as the metallic material of the low melting point. The plating layer 30a is diffused by the plastic flow in a plastic fluid area 20a generated in the aluminum alloy during friction stir welding to diffuse the plating layer 30a, and the steel sheet newly-formed surface 30 of the low melting point steel sheet 30 is exposed and solid phase joining of the surface to the aluminum alloy 20 is performed to obtain the weld joint of the high joint strength. The friction stir welding member is also provided. PCOPYRIGHT: (C)2008,JPO&INPIT