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

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 degrees 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.

Automated summary

SiC/Al-Cu nanocomposites were successfully fabricated via simultaneous solid-state alloying of Cu and dispersing of SiC nanoparticles in Al matrix for the first time. The nanocomposites exhibited excellent mechanical properties at both room temperature and high temperatures, as well as enhanced high-temperature creep resistance. The outstanding performance of the nanocomposites can be attributed to the synergy of solid-solution strengthening and Orowan strengthening. This study demonstrates the high efficiency of the ARB-induced matrix alloying and dispersing of nanoparticles in optimizing the microstructure and mechanical performances of Al matrix composites.