| 摘要 |
PROBLEM TO BE SOLVED: To provide an aluminum alloy for a piston provided with excellent forgeability and excellent mechanical properties at high temperature after forging. SOLUTION: The aluminum alloy is a cast body obtained by solidifying an aluminum alloy comprising, by weight, 7 to 17% Si, 0.5 to 3% Cu, 0.4 to 1.5% Mg, 0.6 to 1.2% Mn, 0.8 to 3% Ni, 0.05 to 0.3% Zr and 0.15 to 1.0% Fe, with inevitable impurities at a cooling rate of 12 to 50°C/s, and its DAS is 2 to 18μm. The alloy may comprise 0.01 to 0.3% Ti, and may comprise 0.01 to 0.3% Sb or 0.005 to 0.1% Be. In the method for forging a piston, the cast body is subjected to previous working at 200 to 240°C at a working ratio of 20 to 45% so as to form an aluminum alloy stock for forging, and the stock is subjected to forging at a temperature above the recrystallization temperature of the aluminum alloy for forging. COPYRIGHT: (C)2010,JPO&INPIT |
