Effects of Deep Rolling Process on Microstructures and Microhardness of Different Laser Cladding Materials Coated on UIC860 Grade 900A Rails

Rail transport is an essential component of global logistics as it supports heavy loads and reduces transportation costs. However, rail tracks often suffer from wear, fatigue, and cracking, which increase maintenance costs and shortened service life. One potential approach to enhance the mechanical properties of rail surfaces is the application of laser cladding (LC) technology combined with deep rolling (DR), which increases the microhardness of the coating layer. This study aimed to examine the effects of four nickel-based cladding materials: Colmonoy 42, Colmonoy 56, Colmonoy 63, and NiCrBSi + 17WC. The experimental results showed that the laser cladding process significantly increased microhardness. Combined with the deep rolling process, Colmonoy 63 demonstrated the best response, achieving the highest microhardness of 943.47 HV, an increase of 24.78% compared to the rail treated with laser cladding. Therefore, the findings of this study indicated that combining the laser cladding process with deep rolling is an effective method for improving the surface properties of rails.