热挤压对搅拌铸造Al—Si—Pb轴承合金磨损行为的影响

Effect of Hot Extrusion on the Wear Behavior of Stircast Al-Si-Pb Bearing Alloys

摘要:

研究了干摩擦条件下铸态与热挤压态Al-Si-Pb轴承合金的磨损行为。研究结果表明：热挤压能有效改善铸态合金的组织，提高机械性能，显著降低气孔率。这些有利因素极大地提高挤压态Al-Si-Pb合金的耐磨性。光学观察与X射线光电子能谱分析（XPS）表明：含铅量超过15％的Al-Si-Pb合金在中等载荷下表现出几乎恒定的磨损率与较好的抗咬合性，其原因是因为在磨损过程中形成一层几乎覆盖整个麻醉损面的润滑膜，该膜是由含Al,Fe,Si,O,Pb等化合物混合组成。

Abstract:

The wear behavior of as cast and hot ex truded Al-Si-Pb alloys was investig ated under dry condition.The results show that the microstructure and mechanical prop erties can be greatly improved and porosity can be decreased significant ly by hot extrusion.These factors increase wear resistance of hot extr uded Al-Si-Pb obviously.Optical ob servation and X-ray photoelectron s pectroscopy(XPS)analysis reveal that the almost constant wear rate at mediate load level and better resistance to seizure for Al-Si-Pb alloys with more than 15%lead are due to a film of lubricant covered almost entire worn surface in the wear.This film is a mixture containing Al,Fe,S i,O and Pb.