Abstract:The Al-based composite friction materials were prepared by powder metallurgy,and the effects of the content and particle size of SiC on the on the properties of composite friction materials were studied.The results show that along with increasing of the of SiC content,the relative density and the bending strength of the composite friction materials are decreased continuously,the friction coefficient is increased gradually,the Rockwell hardness is increased at first and then decreased,and the specific wear rate is decreased at first and then increased.With the increase of SiC particle size,the relative density,bending strength and Rockwell hardness are increased gradually,the friction coefficient is increased at first and then decreased,and the specific wear rate is increased continuously.The Al based composite friction material has stable and moderate friction coefficient and extremely low wear rate when modified by 25% of SiC mass fraction with particle size of 20 μm.