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In order to improve the service life and reliability of aluminum alloy in practical applications, it's usually necessary to prepare coatings on the surface to improve its wear and corrosion resistance. In this study, the Al6061/SiC composite coatings were successfully fabricated on the surface of Al7075 alloy by cold spraying with the different kinds of SiC powder. The influences of SiC contents and particle size on the microstructure, wear and corrosion performance of the composite coatings were analyzed systematically. Results showed that cold sprayed Al6061/SiC composite coatings had dense structure by adding different kinds of SiC particles. Among the coatings prepared by powders with the same SiC ratios, the composite coatings prepared by black SiC possessed the highest content of hard particles and the lowest wear rate under a load of 10 N, while the corrosion resistance of the composite coating was similar. In coatings prepared with different mass ratios of Al6061 and black SiC, as the proportion of SiC increased, the content of hard particles in the coating first increased and then decreased. Meanwhile, the composite coating with ratio of 3:7 had the highest content of hard particles(57.5%) and the lowest wear rate [1.787 6×10^-4 mm³/(N·m)], but its corrosion resistance was not as good as that of other coatings. Moreover, two kinds of powders with the particle sizes of 15～30 μm and >30 μm were obtained by sieving black SiC powder. Mixing Al6061 with these two powders according to the mass ratio of 3∶7, respectively, and the wear properties of the prepared coatings were not as good as those of the original powders, but the corrosion resistance was better than those of the original powders. In addition, the corrosion current density of the coatings prepared by mixing 15～30 μm of black SiC was 9.59×10^-5 A/cm².