The Effect of Laser Scanning Speed on Microstructure and Performance of Cr3C2-NiCr Cermet Fabricated by in-situ Laser Cladding

Abstract

To explore the effect of laser scanning speed on the microstructure and performance of Cr₃C₂-NiCr cermet layers fabricated by in-situ laser cladding, Cr₃C₂-NiCr cermet layers were laser cladded from Ni/Cr/Graphite (25:65:10 wt.%) elemental powder mixtures. The microstructures of the laser cladded cermet layers and the formation mechanism were investigated. In addition, the effect of laser scanning speed on the microstructure, friction and corrosion performance of the Cr₃C₂-NiCr cermet layers was studied. The results indicated that the in-situ laser cladded Cr₃C₂-NiCr cermet layers were composed of NiCr binder and Cr₃C₂. The laser scanning speed had a significant influence on the carbide content, composition and size. Furthermore, it affected the in-situ laser cladded cermet layer’s hardness and wear resistance. The corrosion resistance of the in-situ laser cladded cermet layer was superior to that of laser cladded nickel-based alloy and was improved with decreasing laser scanning speed.