摘要 |
An aluminum alloy material comprising 9.0 to 11.0 mass% Si, at most 0.5 mass% Fe, 0.7 to 1.1 mass% Cu, at most 0.15 mass% Mn, 0.3 to 0.7 mass% Mg, a remainder of Al, and unavoidable impurities undergoes a solutionizing treatment. The material is then cold forged. The material subsequently undergoes an artificial aging treatment. A formed material for a brake piston is thereby obtained |