Optimisation and wear performance analysis of laser-cladded WC-Fe-based coating

Abstract

In this study, a WC-Fe-based coating is prepared on a 45 steel substrate utilising laser cladding technology. To optimise the composition of the Fe-based alloy powder, a thorough analysis of the cracks observed during the formation of the cladding layer is conducted. Elemental control of the WC-Fe-based alloy powder is employed to mitigate issues such as porosity and slagging, consequently reducing the susceptibility to cracking. The optimised WC-Fe-based alloy coating exhibits enhanced wear and abrasion resistance when compared to the widely used Ni45 coating. Microstructural investigations reveal that both coatings feature dendrites, cellular crystals and equiaxial crystals; however, the WC-Fe coating displays a finer and denser microstructure, highlighting its superior characteristics. Hardness and abrasion resistance tests demonstrate the exceptional performance of the WC-Fe-based coatings, having approximately three times the hardness of the substrate and a wear rate approximately seven times lower than that of the substrate. The friction coefficient remains consistently stable for the WC-Fe-based coatings at approximately 0.4, indicative of remarkable friction reduction and abrasion resistance.