Characterizing and Analyzing the Tribological Behaviour of Diamond Coated Tungsten Carbide (WC)

Abstract

In this research work, the deposition of diamond coating was done on the tungsten carbide (WC) substrate utilizing the the thermal Chemical Vapour Deposition (CVD) technique. The carbon precursor used for growing the diamond on the tungsten carbide (WC) substrate material was sugarcane bagasse. The tribological properties of deposited diamond coating were studied examined in this paper. For characterization of the developed coating, Field Emission Scanning Electron Microscope (FESEM), Raman spectroscopy and X-ray diffraction (XRD), were used to characterize the developed diamond coating on the substrate material. These processes were used to confirm the presence of diamond coating on the substrate. For inspecting the hardness of the developed diamond coated and un coated samples, the tests of micro-hardness were also executed. The values of the Vickers hardness for the un-coated and the diamond coated substrates were found to be 964.95 HV to 1457.48 HV respectively. This depicted a rise of 51% in the hardness of the un-coated WC inserts. As per ASTM G-99 standards tribological behaviour of the developed coated substrate was also the scope of this work using a pin-on-disc tribometer. The tribological tests showed improvement in the wear resistance of the diamond coated WC inserts as there was a decrease in the value of wear by 57.84 %. The value of the coefficient of friction (COF) also found to be decreased by 51.48%. This paper presents a combined study of using tribological tests and morphologic study showing the advantages of coating diamond on the tungsten carbide (WC) substrate.