General tendencies of the effect of the abrasive size and shape are already established for abrasion of materials: a coarser abrasive paper leads to high wear rates, and so do more angular abrasive particles. Combined influence of these parameters may however alter the wear behaviour of a material which will depart from these established rules. Tests were carried out to investigate the extent of these effects when a material is submitted to impact and impact-abrasion wear. They showed that the impact wear rate is very dependent on the size and shape of the abrasive. It was also found that the deterioration of the abrasive particles during the impact has a major influence on the abrasion component they produce after the impact. Impact and impact-abrasion tests were carried out on a martensitic high-chromium cast iron (3.05%C, 17.00%Mn-31.9% carbide-62 HRC) with an abrasion pin-test apparatus