To produce a high toughness aluminum casting having high elongation and high impact value, furthermore excellent in tensile strength and proof stress and moreover having corrosion resistance and to,provide a method for producing the same.
This high toughness aluminum casting has a compsn. contg., by weight, 1.65 to 4.0% Si, 0.2 to 0.4% Mg, ≤0.2% Fe, and the balance substantial Al with inevitable impurities, and in which the area ratio of eutectic Si in the aluminum matrix is regulated to ≤15%, elongation to ≥15% and impact value to ≥30 to 40×104J/m2. Further, is a high toughness aluminum casting having characteristics in which the area ratio of eutectic Si in the aluminum matrix is regulated to ≤15%, elongation to ≥15%, impact value to ≥15×104J/m2, tensile strength to ≥220MPa and proof stress to ≥125MPa. As for the compsn., as improvement treating agents, ≤1.0% Sr and/or Ti and ≤1.0% Cu or ≤0.3% Mn may be incorporated therein. As for the method for producing the same, the high toughness aluminum casting is subjected to high temp. solution treatment and is thereafter subjected to aging treatment at 140 to 200°C for 8 to 55hr.
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