untereutektische aluminium silicon alloy with additions of bismuth and tin

摘要

An improved aluminium-silicon alloy having relatively substantial additions of tin and bismuth is provided which is particularly wear-resistant and sufficiently self-lubricating so as to be suitable for use in a wearing component even when poorly lubricated. The relatively high tin and bismuth additions within the alloy co-operate with the other elemental additions so as to provide a sufficiently low-friction bearing surface (or self-lubricity) which significantly enhances the wear-resistant properties of the alloy. In particular, the preferred aluminium alloy is used to form a socket plate (10) which receives high-strength steel bearing members (16) within a compressor unit of an automobile air-conditioning system. The improved aluminium alloy minimizes wear and alleviates galling of the socket plate (10) during use. In addition, the improved aluminium alloy is also characterized by good strength and sufficient ductility so as to permit swaging of the socket plate (10) formed from the alloy around respective balled ends (14) of the high-strength steel bearing members (16). IMAGE