SINTERED AL-SI BASED ALLOY EXCELLENT IN WEAR RESISTANCE

摘要

PURPOSE:To produce a sintered Al-Si based alloy excellent in wear resistance by mixing various metal powders incorporating shell-like Al2O3 with an Al-Si based alloy powder, press-compacting the powder mixture, and then sintering the green compact. CONSTITUTION:A molten Al-Si based alloy containing, by weight, 10-35% Si or further 1-10% Cu or further 0.4-4% Mg or a molten Al-Si alloy containing 10-35% Si and 0.1-10% of one or two more elements among Fe, Ni, Mn, and Cr is pulverized by an air atomizing method. Separately, the powder of Al-Cu alloy, Al-Ni alloy, etc., is subjected to oxidizing treatment in the air, thereby a hard shell-like phase containing Ni-alloy or Cu-alloy powder which incorporates fine shell-like Al2O3 inside is prepared. This powder is mixed with the above-mentioned Al-Si alloy powder, which is press-compacted and sintered in an inert-gas atmosphere. By this method, the sintered Al-Si based alloy having a structure in which hard compound powder grains composed principally of Al2O3 are uniformly distributed by 5-50vol.% and excellent in wear resistance can be obtained.