AbstractInvestigations are reported of the response of an alumina fibre–aluminium metal matrix composite system to wear by two-body abrasion. The wear resistance of the composites was found to range from almost two to six times that of the unreinforced matrix alloy. A transition in wear behaviour was found for the various sizes of abrasive particle. With small particles, the wear resistance of the composite increased with increasing fibre volume fraction and the worn surfaces were relatively smooth. With larger particles, the wear resistance decreased with increasing fibre content above a certain level and, on the worn surfaces, fibre fracture and extensive debonding were observed at the fibre/matrix interface. The effect of abrasive particle size on this transition behaviour may be explained by a theoretical analysis of the fracture of a brittle fibre in a ductile matrix under point loading.MST/872