Fe-based alloy composite coating reinforced by Ti(C_0.3N_0.7)particle through laser cladding technology

A new in-situ synthesis method is carried out to produce Fe-based alloy composite coating reinforced by Ti(C_0.3N_0.7) particle on the Q235 mild steel through CO₂ laser cladding technology.X-ray diffraction is used for phase identification in the composite coating.The microstructure of laser cladding layer is analyzed by means of optical microscopy, scanning electron microscopy, and electron probe microscopy analyzer.The microhardness distribution is measured by using microhardness tester.The results show that Ti(C_0.3N_0.7) particle is produced by an in-situ metallurgical reaction of TiN particle and graphite powder during laser cladding process.The shape of some Ti(C_0.3N_0.7) particle is similar to rhombus, and the others are irregular shape.Size of the fine Ti(C_0.3N_0.7) particles is within 0.1-5 μm, and evenly in dispersed the matrix.The micro-hardness of laser cladding layer is within 600-700 HV0.2, and much higher than that of the matrix.