Microstructure and properties of CeO2 and WC synergistically enhanced laser cladding Ni60 coatings

Abstract

This study investigates the effects of different CeO₂ contents (0.5 wt.%, 1.0 wt.%, 1.5 wt.% and 2.0 wt.%) on the microstructure and properties of 50 wt.%WC-Ni60 coatings to enhance performance, extend the service life of laser cladding coatings on 45 steel. The synergistic mechanisms by which CeO₂ and WC improve the microstructure and properties of the coatings are systematically explored. Microstructural characterization, phase analysis, microhardness testing, wear resistance evaluation, and corrosion resistance assessment were conducted using scanning electron microscopy (SEM), X-ray diffraction (XRD), and electrochemical methods. The results demonstrate that CeO₂ addition significantly refines the grain structure of WC-Ni60 coatings, leading to notable improvements in microhardness, wear resistance, and corrosion resistance. The optimal performance is achieved at a CeO₂ content of 1.0 wt.%: compared with 50 wt.% WC-Ni60 coating, the microhardness increases by 9.3 %, the wear rate decreases by 88.4 %, and the corrosion resistance is significantly enhanced. These improvements are attributed to CeO₂-induced grain refinement, homogeneous distribution of hard phases.