ANALYSIS OF TRIBOLOGICAL FACTORS ON DRY SLIDING WEAR BEHAVIOUR OF THERMALLY SPRAYED CARBIDE AND CERAMIC COATINGS BY TAGUCHI METHOD

摘要

Thermal spray processes are widely used in industries to compensate the worn surfaces of different components used in automobiles. This comes as a means of savings the worn parts by reusing them after they have been thermally sprayed by suitable wear resistant coatings. In this study, the HVOF sprayed (WC-12%CO and Al2O3-13%TiO2) coating is applied to AISI 1040 steel substrate. The surface morphology, composition and phase structure analysis are done with the help of scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD), respectively. The high temperature pin on disc test was used to estimate the wear of the coatings at different process parameters. An orthogonal array and analysis of variance was employed to investigate the influence process parameters on the coatings. The objective is to establish a correlation between the wear of coatings and wear parameters such as load, temperature and velocity. These correlations were obtained by multiple regressions. Finally, confirmation tests were conducted to verify the experimental results foreseen from the mentioned correlations. The data were analyzed and a statistical model, explaining the effects of different parameters as well as their interaction, was obtained. Results shows that wear rate, at room temperatures, of the WC-12%Co and Al2O313%TiO2 are almost same. While at 600C, the wear failure mechanism turns from plastic deformation to fracture resulting from crack propagation.