| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an Al-Mg-Si based aluminum alloy sheet excellent in coating/baking curability and moldability. <P>SOLUTION: The sheet material of an Al-Mg-Si-based aluminum alloy having a composition which contains 0.5-2.0% of Si and 0.2-1.5% of Mg by mass, further contains one, two or more kinds of Cu, Zn, Fe, Mn, Cr, V, Zr, Ti and B, and the balance comprising Al and inevitable impurities is subjected to solution treatment at a temperature equal to or higher than 480°C and equal to or lower than 580°C, is cooled to a quenching temperature below 60°C at a cooling speed equal to or higher than 2°C/second, is held at the quenching temperature for the time equal to or shorter than one hour, and is then subjected to: (1) intermediate preliminary aging of heating it from the quenching temperature to an intermediate preliminary aging temperature equal to or higher by 10°C than a preliminary aging temperature and equal to or lower than 150°C at a temperature elevating rate equal to or higher than 2°C/minute, and holding it at the intermediate preliminary aging temperature for the time equal to or shorter than ten minutes; and (2) preliminary aging of cooling it from the intermediate preliminary aging temperature to the preliminary aging temperature equal to or higher than 50°C and equal to or lower than 140°C at a cooling rate equal to or higher than 2°C/minute, and holding it at the preliminary aging temperature for the time equal to or longer than one minute and equal to or shorter than ten hours. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
