Effect of nano-WC content on microstructures and wear resistance of laser cladding Fe-based alloy coatings

Abstract

Three kinds of Fe-based power with different content of nano-WC were successfully prepared on 35CrMoV steel using laser cladding technique. The influence of nano-WC on the macro-morphology, microstructure and wear resistance of Fe-based coatings under different wear conditions was investigated by scanning electron microscopy and three-dimensional non-contact surface mapping. It has been found that a lot of fine grains and equiaxed grains synthesized with the addition of nano-WC. Both the volume fraction of eutectics and wear resistance of Fe-based coatings are greatly increased with a moderate addition of nano-WC, which is attributed to the exist of the partial dissolution of hard and high temperature WC phase in the composite coating. The wear rates increase more than 2–3 times with the addition of nano-WC range from 5 wt% WC to 10 wt%WC. Hence the addition of nano-WC strengthening phase is an effective and feasible way to improve the mechanical properties, especial for the tribological properties.

Keywords

• laser cladding
• Fe-based alloy
• nano-WC
• microstructure
• wear resistance
• wear rate