| 摘要 |
PROBLEM TO BE SOLVED: To enable joining and weight reduction of a space frame for automobile and a vehicle structure by arranging a backing of the same material as an aluminum member at butting parts and subjecting a butting parts together with the backing to friction agitation joining so as to obtain a joined part wherein strength reduction is small, an overlay is reduced and a strain is reduced. SOLUTION: A backing 1, which has the same material as hollow tubes T1 , T2 , is arranged in the inside of butted parts 1 of the hollow tubes T1 , T2 . The backing 2 is formed to an annular shape from extrusion, drawing, rolling materials. A gap C between inner faces of the hollow tubes T1 , T2 of the butting parts 1 and the backing 2 is preferably made e.g. <=0.5 mm, in the case the gap C exceeds 1 mm, a defect of a tunnel shaped hole is likely formed at a joining part. Further, some taper T is preferably formed on the backing 2. Friction agitation joining of the butt parts 1 is conducted so that a pin 5 is inserted into the butting parts and the backing 2 and horizontally moved along the butting parts while rotting at high speed. |
