Enhanced strength and ductility of Al-SiC nanocomposites synthesized by accumulative roll bonding

Abstract

This paper present experimental study on improving mechanical properties of Al and Al-xSiC nanocomposites (x=1, 2 and 4%) synthesized by Accumulative Roll Bonding (ARB) technique. SEM, EDX and XRD analysis was used to characterize the structural changes in the manufactured materials while tensile and microhardness tests were used to characterize their mechanical properties. Homogeneous distribution of SiC nanoparticles was achieved after five ARB cycles. A significant strength improvement was achieved for processed Al and Al-SiC nanocomposites after five ARB cycles due to grain refinement, grain misorientation and SiC strengthening. The grain refinement and grain misorientation contributed the strength improvement by 161% and 46%, respectively, while the addition of 1% SiC nanopartciles contributed by 78% which is increased to 101% for 4% SiC. The ductility is reduced after the zero ARB cycle however it increased with increasing the number of ARB cycles reaching 8.2 and 5.8% for Al and Al-4% SiC nanocomposites, respectively, after 5 ARB cycles. The fracture shape in the ARBed samples is a combination of necking and shearing with a tendency to shearing shape for Al-SiC nanocomposites.