Study of microstructure and properties of laser cladding TiC-H13 composite coating

As one kind of excellent hot-working die steel, H13 has been widely used. But the surface failure was usually found which can decrease the service life. In this paper, TiC ceramic powders were introduced to strengthen H13 steel by continuous wave CO₂ laser cladding. The macro surface quality and microstructures was investigated by optical microscopy (OM) and scanning electronic microscopy (SEM). Thermal stability and anti-wear performance were measured. TiC was uniformly dispersed in the coating. But the morphologies of TiC in the cladding coating were different for temperature gradient during laser cladding. Near the surface of cladding coating, TiC have been partially molten shown as dendritic structure while in the cladding coating was irregular shape such as subrounded or rhombic. The abrasion resistance of laser cladding TiC-H13 was increased about 3 times than the H13 substrate. The thermal stability of composite coating was a little higher than that of substrate after experiments at 873K.