Interface characteristics and mechanical properties of short carbon fibers/Al composites with different coatings

Three kinds of coatings, Ni, Cu and Al2O3, were obtained on the surface of short carbon fibers (SCFs). The interface characteristics and mechanical properties of SCFs/Al composites with the various coatings were systematically studied in this paper. The results showed that, compared to non-coating, Ni or Cu coating improved the wettability of SCFs and Al melt. However, the harmful phases Al3Ni or CuAl2 generated in interface zone and Al matrix result in the lower mechanical properties. Al2O3 coating protected the SCFs and prevented the harmful reaction of Al and SCFs. The interface of Al/Al2O3/SCF without any other phase was clean and well bonded, and the Al2O3-coated SCFs/Al composite had the highest mechanical properties. The interfacial indentation and fracture mechanism of all the composites were analyzed in detail.