PRODUCTION METHOD FOR ALUMINUM ALLOY PLATE EXCELLENT IN BENDABILITY, AND ALUMINUM ALLOY PLATE EXCELLENT IN BENDABILITY AND PRODUCED BY THE METHOD

摘要

PROBLEM TO BE SOLVED: To produce an aluminum alloy plate which is excellent in bendability and suitable for an automotive body sheet, an automotive part, a mechanical part, or the like.;SOLUTION: In the method for producing the aluminum alloy plate excellent in bendability, an aluminum alloy plate essentially containing 0.5-1.3 mass% Si and 0.25-1.0 mass% Mg is subjected to a solution treatment step and then to a strain-imparting step. The difference in surface hardness (Vickers hardness measured under a load of 1 kg) between before and after the strain-imparting step is 3 Hv or higher. Since a suitable amount of strain is imparted to the Al-Mg-Si alloy plate after the solution treatment step, voids which become crystallization nuclei are generated at the vicinity of grain boundaries; thus, the PFZ width at the vicinity of grain boundaries, which is the propagation route of cracking, is narrowed, giving the aluminum alloy plate excellent in bendability.;COPYRIGHT: (C)2003,JPO