Size Effect of Impact Abrasive Particles on Wear and Surface Hardening Behavior of High-Manganese Steel

The size effect of impact abrasive particles on wear and surface hardening behavior of high-manganese steel was studied. Impact wear tests were carried out on MLD-10 tester with abrasive particle sizes of 6.0-0.75 mm, respectively. The results showed that the impact wear behavior and surface hardening mechanism of high-manganese steel were affected by the size of abrasive particles. A critical size of abrasive particle might exhibit to distinguish the impact wear behavior. When the abrasive particle size was larger than 0.75 mm, the wear mass loss generally showed a decreasing trend with the decrease of the abrasive particle size. Dislocation strengthening and mechanical twinning contributed to the good work hardening behavior. However, effective surface hardening layer could not be formed for sample tested with particle size of 0.75 mm and the wear mass loss was the highest among all the conditions. The weak hardening effect led to the sharp increase of the wear mass loss. Press-in abrasives could be observed on the wear surface when the abrasive particle size was larger than 0.75 mm. The press-in abrasives were peeled off from the wear surface and broken, leaving deep grooves and peeling pits. Material exchange with the sample would occur with the flow of abrasives. A large area of furrow was formed on the wear surface. For particle size of 0.75 mm, aggregated abrasives formed a dynamic buffer layer on the surface and the stress distribution was more even. The formation of buffer layer would lower the effect of the impact load and the work hardening effect could not be fully activated. The mutual extrusion among the abrasives, friction wheel and sample caused plastic deformation of the worn surface during impact test. The present study would help guiding to select the application field of high-manganese steel more precisely.