Three-body abrasion of Al-SiC composites

While many works have been focused on the two-body abrasive wear of aluminu m matrix composites, there are relatively few results on the three-body abr asion performance of these composites. In the present study, the three-body abrasion of aluminum matrix composites reinforced with silicon carbide par ticles (SiCp) has been investigated. The metal matrix composites (MMCs) wer e fabricated by a powder metallurgy route involving a final hot extrusion s tep, with Al 1100 matrix and alpha-SiCp reinforcement with mean sizes of 10 , 27 and 43 mu m, in the proportions of 5, 10 and 20 vol.%. Using a wet mon olayer tester, three-body abrasive wear tests were conducted under a consta nt load against silicon carbide and alumina abrasives with four different g rits of 320, 400, 600 and 1000. The microstructural characterizations were performed using light microscopy. The dominant wear mechanisms were identif ied using scanning electron microscopy. The influence of type of the abrasi ve particles on wear rate and dominating wear mechanism is reported. Relati onships between size and volume fraction of the SiCp reinforcement and wear rate is discussed. It is shown that SiCp reinforcement increases the abras ion resistance against all the abrasives used. This increase is generally h igher against alumina than silicon carbide abrasives. (C) 1999 Published by Elsevier Science S.A, All rights reserved.