Research on Wear and Corrosion Resistance of Ni60-WC Coating Fabricated by Laser on the Preheated Copper Alloy

The copper alloy is widely used to prepare pipes in ocean engineering. The surface is washed and corroded by seawater for a long time, which gradually shortens the service life of the condenser tube. In order to improve the wear and corrosion resistance of copper alloy, a Ni60-WC coating was fabricated on a preheated copper alloy by laser cladding. Experiments on the Ni60-WC coatings were carried out by SEM, XRD, Vickers-microhardness meter, wear tester and electrochemical workstation. The microstructure, phases, hardness, wear and corrosion resistance were investigated. The results show that from the top to bottom, the microstructures were columnar dendrites, dendritic crystals and grains, respectively. The wear rate of the Ni60-WC coating was only 4.9 × 10−5 mm3·N−1·m−1, which was only 1.14% of copper substrate. In addition, the corrosion current density was 2.34 × 10−7 mA·mm−2, which was much lower than that of copper alloy substrate (1.14 × 10−6 mA·mm−2). The experimental results show that this Ni60-WC coating has a good metallurgical bonding and hardness, and it also has good wear and corrosion resistance, which is helpful to improve the service life of the condenser tube.