Two-body abrasive wear of Al-SiC composites

The two-body abrasive wear behaviour of aluminium matrix composites reinfor ced with silicon carbide particles has been investigated. The metal matrix composites were fabricated by a powder metallurgy route involving a final h ot extrusion step, with Al 1100 matrix and alpha-SiCp reinforcement with me an sizes of 10, 27 and 43 mu m. in the proportions of 5, 10 and 20 vol.%. U sing a pin-on-disc apparatus, two-body abrasion tests were carried out agai nst silicon carbide and alumina abrasives with four different grit sizes, T he microstructural characterisations were performed using light microscopy. The dominant wear mechanisms were evaluated using scanning electron micros copy, It was shown that SiCp particles reinforcement improved the abrasion resistance against ail the abrasives used. This improvement generally was h igher against alumina than against silicon carbide, The abrasion resistance increased with an increase in the volume fraction and size of SiCp particl es reinforcement. The results also showed that the abrasion resistance decr eased with increasing the relative abrasive penetration depth, until a crit ical value: above this limit the abrasion resistance was generally independ ent of the penetration depth. (C) 1999 Elsevier Science S.A. All rights res erved.