Effect of in-situ SiC particles on the room–temperature dry sliding wear behavior of Al–12Si–4Cu–2Ni–1Mg alloys

In-situ SiC particles (SiC_ip) show significant potential to elevate the wear behavior of Al matrix composites due to the improved SiC/Al interfacial bonding. This study mainly focuses on the effect of SiC_ip on the room–temperature dry sliding wear behavior of Al–12Si–4Cu–2Ni–1Mg (Al–Si–Cu) alloys under a widely ranged 40–160 N load. SiC_ip/Al–Si–Cu composites and Al–Si–Cu matrix alloys were obtained via a melt method, with the powder metallurgy Al–12Si-18SiC_ip composites as the master alloy. The variation pattern of the wear loss and friction coefficient of the composites and the matrix alloys have been explored, the microstructure of the friction surface and the wear debris have been observed, and the wear enhancing and interfacial improving mechanism of SiC_ip have been discussed. Results show that the wear of SiC_ip/Al–Si–Cu composites change from mild-to-moderate wear to severe wear at the load 120–160 N. The severe wear of the composites can be marked by the frequent appearance of large lamellar debris. Due to the improved SiC/Al interfacial bonding, SiC_ip can undergo plastic flow and accumulate at the friction surface during wear, so simultaneously improve the wear resistance and friction coefficient of Al–12Si–4Cu–2Ni–1Mg alloys, especially at high loads. For in-situ coating SiC_ip, the tress–buffer effect of in-situ coating plays an important role during wear.