Effect of high temperature (550oC) on tribological properties of Eco-friendly carbon based composite coating for piston ring application

The aim of present work was principally concern to establish a correlation between tribological performances with inherent eco-friendly carbon based composite coating under dry condition, using HVOF thermal spray deposition technique for piston ring application. FESEM-EDS was employed to depict microstructure and surface morphology, while micro-Raman spectrometer was used to analyze carbon peak of composite coating. In order to confirm the phase deposition, coated samples were probed using HRXRD. Vickers micro-hardness, XRD residual stress, and corrosion test were used to compute the adhesion, quality, and performance of the developed composite coating. The tribological performance of developed composite coating was examined by high temperature rotary tribometer, to explore the wear behavior of eco-friendly Carbon based composite coating from 30 to 550^oC with constant load and sliding velocity of 20N and 0.3m/s respectively. The experimental result shows that composite coating was temperature dependent and enhanced micro-hardness (520 HV), lowest residual stress (102 MPa), COP (0.2), wear (130 micron) and frictional force (4N) were obtained at higher temperature (550^oC), due to formation of tribo-oxidative films and strong adhesion strength or due to graphitization effect under dry condition.