Microstructure and wear properties of in situ multiple carbides reinforced Fe based surfacecomposite coating produced by laser cladding

摘要

In situ multiple carbide of TiCzd-(Ti,V)C reinforced Fe based surface composite coating was produced by laser cladding melting a precursor mixture of graphite, ferrotitanium (Fe–Ti) and ferrovanadium (Fe–V) alloy powders on AISI 1045 steel substrate. The microstructure and wear properties of the composite coatings were investigated by scanning electron microscopy and Xray diffraction, as well as dry sliding wear tester. The results showed that the surface composite coating consisted of in situ TiC+δ-(Ti,V)C carbides and a-Fe matrix. TiC+δ-(Ti,V)C carbides with cubic or radial dendrites shape were synthesised during laser clad processing, and the carbide particles uniformly dispersed in the matrix. d-(Ti,V)C is carbide with V dissolved in the TiC structure. The introduction of ferrovanadium leaded to reduce the size of carbide particles. The multiple carbides of TiC+δ-(Ti,V)C created a higher microhardness and more excellent wear resistance than TiC on its own would under dry sliding wear test condition.