It is difficult for copper-based friction materials(CFM)to exhibit both high coefficient of friction and exceptional wear resistance when mated with C/C-SiC composites under high-speed braking conditions.In this research,copper-based friction materials reinforced with short-cutting pitch-based carbon fibers(CFM-CF)were prepared by powder metallurgy,and the mechanical,thermal and tribological properties of CFM-CF were investigated.The results show that at room temperature,the Brinell hardness,thermal diffusion coefficient and specific heat capacity of CFM-CF increase by 14.8％,9.5％and 6.8％,respectively.Under high-speed braking condition(6 000 r/min),the friction coefficient and stability coefficient of CFM-CF increase by 25.0％and 6.1％,respectively,and the wear loss decreases by 42.2％.The improved flatness of worn surface and formation of stable mechanical mixing layer as well as the dropped diameter of wear debris contribute to the superior wear resistance of CFM-CF.The wear mechanism of CFM-CF changes from abrasive wear and adhesive wear to oxidation wear and fatigue wear with the increase of speed.
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