Enhancing the Mechanical Properties of Copper with WC Coating through Electro-Spark Deposition (ESD)

Ceramic coatings are able to increase the hardness and tribological properties of any substrates especially soft metallic substrates. Copper is used in electrode of Resistance Spot Welding (RSW) and due to its intrinsic properties, it has low mechanical properties. Tungsten Carbide coatings applied to copper electrode by Electro Spark Deposition (ESD) process. The obtained coat was evaluated and the consequent increase in hardness of the copper substrate measured by micro Vickers hardness tester. The maximum hardness was obtained at 50 current and 10 kHz frequency. Results show that with increasing the frequency and current, hardness value is increased. Microstructure evolution of the coating and substrate/coating interface investigated through Scanning Electron Microscope (SEM). The SEM image showed rough surface of the coating. There was mutual elemental diffusion in the substrate/coating interface. There was not any major segregation in the interface.

Keywords:

Ceramic coatings , WC , Tribological properties , Electro Spark Deposition (ESD)