Investigation of physical, mechanical and corrosion properties of copper carbide surface composites produced on copper surface

This thesis aims to improve the tribological properties of copper and to minimize its alteration of electrical properties. For this reason, copper carbide surface composites on electrolytic copper are coated with plasma spray coating method. SiC, B4C and WC-Co were used as carbide. These carbides have been added 5%, 10% and 20% by weight to investigate the effect on tribological, corrosion and physical properties. For the tribological properties, Ball-on-Flat Sliding wear method is used. Potentiodynamic method was used for corrosion. For the microstructure properties and phase composition of the produced coatings, optical microscope, SEM-EDS and XRD analyzes were used. The electrical conductivity of the coating layers is based on the eddy currents principle. It can be observed that silicon carbide and boron carbide are decomposed in the result of XRD analyses, SEM-EDS, and Mapping analyses. Also, at tungsten carbide-cobalt Co6W6C, W2C and WC phases were detected through XRD analyses. The hardness values of all coatings are higher than the hardness of the substrate. Hardness values increased with increasing rate of additive in each coating. The highest hardness value is tungsten carbide-cobalt. Also, it can be seen that the hardness value of tungsten carbide-cobalt is approximately 1.8 times of the hardness value of the substrate material. Both abrasive and adhesive wear types were observed in the copper substrate and coating layers. The increase of the load in all samples cause a rise of the loss of material. Through the examinations of corrosion results of all samples, it is observed that the lowest current density is in the uncoated substrate material. Coating the samples increased the current density. The results of electrical conductivity tests decrease with the increase in carbide ratio in the coating. At the same time, the increase in the amount of additive in the coating also caused the increase in porosity.