The worn surface of the PM steel after exposure to the G65 test is shown in Fig. 8a. By comparing with Fig. 4a, it is seen that the matrix has been selectively removed by the abrasives and that the surface is now covered by V and Cr carbides. This is due to the fact that the hardness of the carbides and the matrix are, respectively, higher and lower compared to the abrasive particles. There are no apparent wear tracks that indicate microcutting or microplouging which is explained by the dense distribution of fine V and Cr carbides.