Effect of B4C and SiC nanoparticle reinforcement on the wear behavior and surface structure of aluminum (Al6063-T6) matrix composite

In this study, boron carbide -(B4C) and silicon carbide (SiC) nanoparticle reinforced aluminum matrix composites (AMC) were fabricated by stir cast method. The morphology of the SiC and -B4C nanoparticles are analysed by scanning electron microscope (SEM). The Electron probe microanalysis and energy dispersive spectroscopic analysis were employed to confirm the dispersion of nano SiC and -B4C particles in the aluminum matrix. The abrasion wear behavior of these composite materials was investigated under normal loads of 10 N, 20 N and 30 N. The effect of reinforcing materials on wear behaviour was investigated and the reinforced composites exhibits relatively high wear resistance compared to pure Al6063-T6 alloy. Wear resistance of the -B4C reinforced AMCs was relatively higher than that of SiC reinforced AMCs at all the applied loads. SEM images of the worn surfaces revealed that micro fracture of the reinforcement composites was the predominant mechanism associated with 3 body abrasion wear. Moreover, SEM images revealed that the debris and detached particle formations are more in the nanoparticle reinforced AMCs. A strong interfacial interactions between Al matrix and SiC nanograin with strong Al-Si bonding is responsible for the high wear resistance. The wear mechanism is varied from abrasive to oxidative by increasing the normal load in all the samples. Moreover, the formation of a condensed spinel structure with the consistent matrix/particle interface bonding provides a substantial particle strengthening effect.