Effect of Laser Cladding Stellite 6-Cr3C2-WS2 Self-Lubricating Composite Coating on Wear Resistance and Microstructure of H13

Abstract

In order to prevent the wear failure of the hot-working die, the composite coatings of Stellite 6-Cr3C2-WS2 was fabricated on H13 hot-working die steel by laser cladding. The composite coating was prepared through the in-situ generation technology, that can give H13 the ability of self-lubricating at the working temperature (about 200 °C). The effect of the various WS2 percentages on the properties of the coating was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), microhardness test, friction and wear test. In addition, the phase constitutions, microstructures and wear properties were also investigated systematically. The obtained hardness of the cladding coating is approximately 2.5 times higher than the substrate because of the constituents of γ-(Fe, Co)/Cr7C3 eutectic colony, (Cr, W)C carbide and dendritic crystals in the coating. Furthermore, the friction coefficient decreases to 70% of the substrate due to the CrS self-lubricating phase. The analyses results suggest that an 85% Stellite 6-10% Cr3C2-5% WS2 composite coating has excellent material properties.