Effect of Chromium Nitride on Microstructure and Properties of Fe-Based Coating by Laser Cladding

In this paper, the Fe-based cladding layer was prepared on 42CrMo substrate by laser cladding mixture containing chromium nitride. The effects of chromium nitride on microstructure and property of cladding layer were studied. The experimental results indicate the chromium nitride is unstable during the process of laser cladding. It is very difficult to obtain chromium nitride in the laser cladding layer. However, the addition of chromium nitride in cladding powders could promote the formation of austenite phase, and increase the microhardness of cladding layer. The reason about increasing the microhardness of cladding layer is the formation of little carbide and solution strengthening of nitrogen, not the strengthening from chromium nitride.