Microstructure and wear resistance of laser cladding WC particles reinforced composite coatings

The wear resistant composite coatings reinforced by WC particles were fabricated by laser cladding using blends of WC particles with large size and TA15 powders as the raw materials. Microstructure and worn surface morphologies of the coatings were analyzed and characterized by optical microscopy (OM), scan electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). Wear resistance of the coatings was evaluated under two-body abrasive and dry sliding wear test condition at room temperature. The results show that WC particles have a uniform distribution in the coatings, which consists of the primary phase (TiW)C/TiC and (TiW)C+(Ti, W) eutectic phase as the matrix. Under two-body abrasive and block-on-ring dry sliding wear conditions, compared with titanium alloy substrate, the wear-resistance of coatings has improved dozens to one hundred times. High hardness of WC particles and the tough matrix with excellent anti-adhesion properties play a key role in improving wear resistance of the coatings.