Tribological properties of Al7075-SiC nanocomposite prepared by hot dynamic compaction

Abstract

Wear resistance of Al7075-SiC nanocomposite prepared by hot dynamic compaction was investigated in this article. Mechanically milled micro-sized Al7075 with different amounts of SiC nanoparticles (SiCnp), 0, 5, and 10 vol%, were used to fabricate the samples. Dynamic compaction was conducted at the strain rates of about 103 s−1. A mechanical drop hammer was used to fabricate the nanocomposite samples with relative density of up to 98%. The microstructural and mechanical behaviors of the samples, such as microhardness and stress–strain curves, were also investigated. The results showed improvement in microhardness and compressive strength of the material. The improvement is believed to be mainly due to the Orowan mechanism rather than the grain refinement described by the Hall–Petch effect. The results also revealed reduction in wear resistance as SiC reinforcing particles increased. The microstructural study of the eroded surfaces indicated that the abrasive and delamination were the dominant wear mechanisms.