Study on the Microstructure and Properties of Nickel-Coated WC Reinforced Nickel-Chromium-Based Alloy Coatings

Abstract

In order to improve the microhardness， impact performance， and water erosion resistance of 0Cr17Ni4Cu4Nb steel， a nickelchromium-based alloy coating containing nickel-coated WC was prepared on 0Cr17Ni4Cu4Nb steel surface using laser cladding technology.A mixture of nickel-chromium-based alloy powder and nickel-coated WC powder was used as the material.The effects of different laser powers on the microstructure， phase composition， microhardness， impact performance and water erosion resistance of the coating were investigated.Results showed that the microstructure of the nickel-coated WC reinforced coating was dense， and the phases included NiCr solid solution，Cr23C6， Fe3W3C， Fe6W6C， and WC.As the laser power increased， the coating's microstructure was refined， and the microhardness， impact absorbed energy， and water erosion resistance were enhanced simultaneously.When the laser power was 1 500 W， the microstructure refinement was most pronounced， showing high hardness， toughness， and water erosion resistance.The coating achieved a hardness of 801 HV0.3，impact absorbed energy of 60.2 J， and a weight loss due to water erosion of 0.106 g.These results demonstrated that the coating prepared at 1 500 W exhibited superior overall performance compared to other coatings and the substrate.

Keywords

• laser cladding； nickel-chromium-based alloy coating； nickel-coated wc powder； phase composition； microhardness； impact absorbed energy； water erosion