METHOD FOR PRODUCING Al-Mg-Si ALLOY EXCELLENT IN BAKE-HARDENABILITY AND HEMMABILITY

摘要

[PROBLEMS] To provide a method for producing an aluminum alloy plate excellent in bake-hardenability and hemmability at a low cost by the employment of a very short production process. [MEANS FOR SOLVING PROBLEMS] A method for producing an aluminum alloy plate, which comprises providing an aluminum alloy melt having a chemical composition, in wt %, that Mg: 0.30 to 1.00 %, Si: 0.30 to 1.20 %, Fe: 0.05 to 0.50 %, Mn: 0.05 to 0.50 %, Ti: 0.005 to 0.10 %, optionally further one or more of Cu: 0.05 to 0.70 % and Zr: 0.05 to 0.40 %, and the balance: Al and inevitable impurities, casting the alloy melt into a slab having a thickness of 5 to 15 mm by the twin belt casting method with a cooling speed at 1/4 of the thickness of the slab of 40 to 150°C/s, winding up a coil, subjecting the coil to a homogenizing treatment, cooling the resultant coil to a temperature of 250°C or lower with a cooling speed of 500°C/hr or more, followed by cold rolling, and then subjecting the resulting product to a solution treatment.