TiC/Ni3Al Composite Coating Synthesized in situ on a Steel and Slurry ErosionWear Resistance

A TiC/Ni3Al intermetallic matrix composite coating was fabricated on a steel by gas tungsten arc welding.The microstructure and properties of the coating were investigated.The formation mechanism and erosive wear mechanism of the coating were also discussed.The results show that TiC/ Ni3Al coating formed on the steel without any intermediate phases and the distribution of TiC particles is homogeneous.The hardness and the number of particles of the coating increased with increasing(Ti+C) content in the preform.The interface between the coating and steel substrate has a good metallurgical bonding.The morphology of TiC particles changed from fine spherical to equiaxial and then to dendritic shape.From the coating surface to the interface,the distributions of Al,Ni,and Fe are gradual variation.However,Ti exists in the coating in the form of TiC particle.The composite coating has obviously lower mass loss than that of H13 and 0Cr13Ni5Mo steels at any impact angle,showing superior erosion resistance.