ALLOY HAVING EXCELLENT RESISTANCE AGAINST THERMAL FATIGUE, ALUMINUM ALLOY HAVING EXCELLENT RESISTANCE AGAINST THERMAL FATIGUE, AND ALUMINUM ALLOY MEMBER HAVING EXCELLENT RESISTANCE AGAINST THERMAL FATIGUE

摘要

The alloy having excellent resistance against thermal fatigue comprises a metal matrix and heat-resistant particles X dispersed in the matrix and having a shorter diameter of less than 20 mu m and a longer diameter of less than 50 mu m, the heat-resistant particles being contained in an amount of 5 to 25 % by volume, and the thermally unstable deposited particles being contained in said matrix in an amount of not more than 1 % by weight. The aluminum alloy having excellent resistance against thermal fatigue contains 4 to 12 % by weight of Si, not more than 0.2 % by weight of Cu, and not more than 0.2 % by weight of Mg, the remainder being aluminum and impurities. The aluminum alloy member forms a highly resistant portion against thermal fatigue by padding said alloy on the surface of the aluminum alloy base metal where thermal strain concentrates.