New Functional-Gradient TiB–TiC–BC–WC Coating Formed by the Method of Laser Cladding

Abstract

We study the coatings formed by the procedure of laser cladding of a powder mixture based on titanium carbide with addition of particles of boron and tungsten carbides on a substrate of VT8 alloy. In the deposited coating metal, we reveal the formation of TiB as a result of melting of boron and titanium carbide particles whose size did not exceed 30 μm. The application of a specially prepared powder mixture (TiC + 5 wt.% BC + 3 wt.% WC) for the deposition enables us to detect solid particles of tungsten carbide playing the role of additional crystallization centers in the deposited metal of the coating, as well as particles of boron and titanium carbides whose sizes exceed 30 μm. In this case, we use the impulsive mode of operation of the laser with a power of 5 kW.