| 摘要 |
<P>PROBLEM TO BE SOLVED: To manufacture an Al-Mg series alloy sheet excellent in a formability and a shape-fixability without applying a stabilizing treatment. <P>SOLUTION: In a method for manufacturing the aluminum alloy sheet for automobile, excellent in a press-formability, surface roughness resistance and shape-fixability; molten metal composed, by mass, of 3.0-3.5% Mg, 0.05-0.3% Fe, 0.05-0.15% Si, and further, regulated to <0.1% Mn and the balance Al with inevitable impurities, is cast into a thin slab having 5-15 mm thickness with a twin-belt type caster so that the cooling speed at 1/4 thickness becomes 20-200°C/sec, and after winding into a coil, a cold-rolling is applied at 60-98% cold-rolling ratio with the rolls having 0.2-0.7 μm Ra of the roll surface roughness, and after applying the finish-annealing at 400-520°C holding temperature with CAL (a continuous annealing line) or 300-400°C holding temperature with a butch-type annealing furnace, this stress-correction is performed with a leveller. <P>COPYRIGHT: (C)2012,JPO&INPIT |
