Effect of laser cladding on wear and damage behaviors of heavy-haul wheel/rail materials

• Wheel/rail rollers suffering laser cladding form uniform and compact coating.
• High hardness of cladding coating markedly alleviates wear of heavy-haul rollers.
• The cladding coating effectively alleviates surface damage of wheel/rail rollers.
• The laser cladding coating can effectively prolong wear life of wheel/rail.
• Laser cladding technology can be used to treat and re-repair damaged wheel/rail.

The objective of this study is to investigate the effect of laser cladding coating on wear and damage behaviors of heavy-haul wheel/rail materials by means of a laboratory-scale rolling–sliding wear apparatus. The results indicate that the wheel/rail rollers with laser cladding form a uniform and compacted coating without any cracks or stomata. The laser cladding coating markedly improves wear-resistance of wheel/rail rollers. The wear mechanism of wheel/rail rollers undergoing laser cladding is plowing and abrasive wear. However, the wheel/rail rollers without laser cladding exhibit visible adhesion wear and serious spalling damage. Furthermore, there are obvious fatigue cracks in both the surface and subsurface. Excellent wear-resistance of laser cladding coating can effectively alleviate surface damage and prolong wear life of heavy-haul wheel/rail. However, further work should be carried out for clarifying the fatigue characteristic of wheel/rail with laser cladding coating.