Achieving enhanced mechanical properties of SiC/Al–Cu nanocomposites via simultaneous solid-state alloying of Cu and dispersing of SiC nanoparticles

Abstract

In this study, SiC/Al–Cu nanocomposites were fabricated via simultaneous solid-state alloying of Cu and dispersing of SiC nanoparticles in Al matrix, for the first time. We showed that a complete solid solution of Cu (4.5 wt%) and a uniform dispersion of dense (up to 15 vol%) SiC nanoparticles in Al matrix can be successfully achieved, by accumulative roll-bonding (ARB) of pure Al, Cu and SiC nanoparticles to high cycles. The as-prepared SiC/Al–Cu nanocomposites exhibited excellent mechanical properties at room temperature and at 300 °C. The microhardness and tensile strength of the SiC/Al–Cu nanocomposites were both significantly increased by incorporating Cu solutes and dense SiC nanoparticles, surpassing those of other Al–Cu matrix composites. The SiC/Al–Cu nanocomposites also exhibited enhanced high-temperature creep resistance with the increase of SiC content. The synergy of solid-solution strengthening and Orowan strengthening was responsible for the excellent mechanical properties of the nanocomposites. Our study indicated the high efficiency of the ARB-induced matrix alloying and dispersing of nanoparticles for optimizing the microstructure and mechanical performances of Al matrix composites.