Two-body abrasive wear of Al–SiC composites

Abstract

The two-body abrasive wear behaviour of aluminium matrix composites reinforced with silicon carbide particles has been investigated. The metal matrix composites were fabricated by a powder metallurgy route involving a final hot extrusion step, with Al 1100 matrix and α-SiC p reinforcement with mean sizes of 10, 27 and 43 μm, in the proportions of 5, 10 and 20 vol.%. Using a pin-on-disc apparatus, two-body abrasion tests were carried out against silicon carbide and alumina abrasives with four different grit sizes. The microstructural characterisations were performed using light microscopy. The dominant wear mechanisms were evaluated using scanning electron microscopy. It was shown that SiC p particles reinforcement improved the abrasion resistance against all the abrasives used. This improvement generally was higher against alumina than against silicon carbide. The abrasion resistance increased with an increase in the volume fraction and size of SiC p particles reinforcement. The results also showed that the abrasion resistance decreased with increasing the relative abrasive penetration depth, until a critical value; above this limit, the abrasion resistance was generally independent of the penetration depth.