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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.