FRICTION STIR WELDING METHOD AND STRUCTURE MANUFACTURED BY ASSEMBLING VARIOUS MEMBERS SUCH AS ALUMINUM ALLOY MEMBERS WITH FRICTION STIR WELDING

摘要

PURPOSE: A friction stir welding method and a structure are provided to prevent the dent in the joint portion in spite of gap between members in bonding metal members such as aluminum alloy by forming the thick portion protruded for a rotating member in the joint portion. CONSTITUTION: Hollow frame members(50,60) formed by extruding aluminum alloy are composed of plates(51,52,61,62) and ribs(53,63) connected to the plates. The end of the hollow frame member is inserted to the end of the other hollow frame member, and a vertical plate(54) for bonding the plates is placed near the end of the hollow frame member. Protruded parts(56,66) are formed by thickening the ends of the hollow frame members to be jointed. The outside of the protruded part is flattened, and inclined for the outside of the plate. A small round rod(72) of a rotating tool(70) is inserted to the joint portion, and a boundary(73) between a large round rod(71) and the small round rod is placed between the extension of the protruded part and the apex of the protruded part. The gap between the ends of the first and second members is filled by relatively moving the rotating tool along the joint portion.