METHOD FOR JOINING ALUMINUM ALLOY MATERIAL AND ALUMINUM ALLOY PANEL MANUFACTURED BY THE METHOD FOR JOINING THE SAME

摘要

PROBLEM TO BE SOLVED: To prevent color difference from being caused between a part corresponding to a joining part and a part corresponding to the other part in a coating to be formed at a surface of an aluminum alloy material that is integrally joined.;SOLUTION: The aluminum alloy material of a lid material 2 and a side material 3 that are to be integrally joined is 5000 series alloy including second phase particles with a particle diameter of ≤5 μm whose distribution density v is 10,000 ≥v (pieces/mm²). Friction stir welding is carried out to a joint part 5 of the ends under such conditions that a diameter d of a shoulder 10 of a tool 8 is 3≤d≤8 (mm) and the number r of rotations of a tool 7 is 0.5≤r≤6 (rotation/mm, the number of the rotations of the tool per joint length of 1 mm), so that difference of the distribution of the second phase particles is hardly made between the joining part and the other part, and accordingly difference of variation of pit formation by etching is reduced and the occurrence of the color difference at the coating of the surface is prevented.;COPYRIGHT: (C)2011,JPO&INPIT