Sliding wear behaviour of carbide-free bainite and martensitic steel

The interactions between the brake disc and the wheel (railway or automobile) can best be represented by sliding wear. Materials having good wear resistance properties are useful to avoid the frequent repairing or replacement of either of these components. In this study, sliding wear behaviour of carbide free bainitic steel and martensitic steel, both having the same composition but processed differently to develop two microstructures, were evaluated. The topography of the worn surface and microstructural change near the worn surface along with the extent of material loss have been studied. It was observed that the crack formation tendency on surface and subsurface of martensitic steel was enhanced as compared to carbide free bainitic steel. The wear mechanism was also changed from primarily adhesion to ploughing and micro-cutting.