Effects of VC content on microstructure and properties of Co-based WC coatings deposited by laser cladding

Abstract To investigate the effect of VC content on the microstructure and phase composition of the coating. Co-WC coatings with different VC contents (0%, 0.5%, 1%, and 1.5%) were prepared on the surface of H13 steel using laser cladding technology. The experimental parameters include: laser power 1600 W, scanning speed 3 mm s −1 , powder feed rate 12 g min −1 . The specimens were analyzed using equipment such as a field emission scanning electron microscope (SEM), an energy dispersive x-ray spectrometer (EDS), and an x-ray diffractometer (XRD) to study the effect of VC content on the microstructure and phase composition of the coating. Subsequently, the coatings were characterized using a Vickers microhardness tester and a friction and wear testing machine. Results showed that incorporating 1% VC into the coating effectively refines grain size while significantly enhancing its mechanical properties. The average microhardness increased from 730 HV 0.5 to 836 HV 0.5 , while the average coefficient of friction decreased from 0.46 to 0.36. At the same time, the wear surface also undergoes a transition from severe oxidation wear and plastic deformation to mild abrasive wear, with a reduction in debris accumulation and adhesion. VC refines coating grain size, enhancing its compactness and wear resistance. At a VC content of 1%, the coating’s microhardness increases by 14% while the average coefficient of friction decreases by 0.1, demonstrating excellent wear resistance.