Influence of WC ceramic particles on structures and properties of laser cladding Ni50-WC coatings

Abstract

This study reported the fabrication of Ni50 and Ni50-WC coatings while employing the laser cladding manufacture (LCM) technique. The surface and cross-sectional morphologies, microhardness, phase structure, corrosion, and wear resistances of the coatings were measured using a scanning electron microscope (SEM), stereoscopic microscope, X-ray diffractometer (XRD), microhardness tester, electrochemical workstation, and friction and wear tester. These results illustrated the emergence of γ-(Ni, Fe), WC, W2C, M23C6, M7C3, and Ni3Fe phases in Ni50–10WC and Ni50–20WC coatings. Besides, W and C contents were higher in Ni50–20WC coating than that in Ni50–10WC coating. The average microhardness of the Ni50–10WC and Ni50–20WC coatings was 655.2 HV and 817.9 HV, respectively, which tripled or quadrupled the substrates' average microhardness. Among all coatings, Ni50 had the lowest corrosion potential value of −0.83 V, indicating poor anti-corrosion efficiency. Ni50–10WC and Ni50–20WC coatings had wear depths of approximately 13.1 μm and 8.3 μm, respectively indicating the outstanding wear resistance of all coatings. Furthermore, the Ni50–20WC coating exhibited the lowest average friction coefficient (0.41) of all coatings because of its fine and compact structure.

Keywords

• Laser cladding manufacture
• Ni50-WC coating
• Phase structure
• Corrosion
• Wear resistance