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Energy can be saved by enhancing the service life of machinery and by designing lighter units. These design changes enable, for example, lower fuel consumption and larger payloads. The implementation of this kind of solutions, however, requires development of better wear resistant materials. In this study, the wear resistance of a structural steel and three grades of wear resistant steel was evaluated with granite abrasive in tests simulating the conditions in heavy machinery in mining and transportation. Two high-stress abrasion and one impact-abrasion wear testing methods were used. In all tests, higher hardness led to decreased mass loss, but in impact-abrasion the hardness dependence was smaller than in the heavy abrasion tests. This may, however, at least partly result from deformation of softer materials over the sample edges, which is not shown as mass loss. Wear surfaces of structural steel samples exhibited the highest degree of plastic deformation due to their lower hardness and higher ductility compared to the wear resistant steels. On the other hand, in harder materials the scratches were more visible, indicating a change in wear mechanism. Both differences and similarities in the behavior and wear mechanisms of the selected steels were observed in the applied conditions.

The role of edge wear was studied in impact-abrasion testing conditions with an impeller-tumbler type test device. Three steels with different mechanical properties were tested at 30° and 90° sample angles using natural granite stone as abrasive particles. The edge and planar (inner) areas were carefully exposed to the same conditions by using tightly fitted two-part samples to obtain relevant information about the differences in their wear behavior. The role of edge-concentrated wear was dominant in all materials, and the edge wear rate was several times higher than the wear rate of the inner parts of the specimens. The difference in wear rate was particularly large in short tests and with the 90° sample angle. However, the dominance of the edge-concentrated wear decreased as the test duration became longer. The wear mechanism was largely microfatigue in all materials, but the samples tested at the 30° sample angle showed more microcutting in comparison to the 90° samples. Moreover, the role of microcutting was higher in the wear of the edge parts than in the inner parts.