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The wear resistant composite coating of two classes of different sized WC particles (-300 mesh and -20～+30 mesh) with Cu-Zn-Sn-Ni filler metals was prepared on the surface of Q235A steel by furnace brazing and protected by flux. Through orthogonal test and one-factor experiment, the factors on coating-forming properties were analyzed. With the aid of microscope SEM and wear test, the coating was analyzed on the microstructure, mechanical properties, bonding strength, wear resistance and mechanism of the Cu-based brazing coating reinforced with WC particles, which process have been optimized.Through analying the factors on coating-forming properties, the result showd, heating temperature and time,-300 mesh WC content had a significant effect on the coating, adding -300 mesh WC, the original microstructure of the coating was changed from needle to dendrite; raising the temperature and extending the time in the heat, the consistency of the coating was improved; but to 910℃, it would produce pores.Optimized results showed:the microstructure of the coating, with 6 wt.%-300 mesh WC,30 wt.%,40 wt.% or 50 wt.% -20～+30 mesh WC, for 10min in 870℃, achieved the lowest porosity. Through analying mechanical properties, bonding strength, wear resistance, it showed, the Cu-based brazing coating reinforced with WC particles could greatly improve the wear-resisting performance of the matrix surface, and the more-20～+30 mesh WC in the coating, the better the wear resistant.
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