Characterization of Nanofinished WC-Co Coating Using Advanced 3D Surface Texture Parameters

Abstract

WC-Co coatings are extensively used in abrasion, sliding, and erosion resistance applications for its favourable mechanical properties. Nanofinishing of WC-Co coating is required for aircraft landing gear cylinder and diesel engine cylinder. Characterisation of surface topography becomes an important aspect in tribological applications as it has significant effect on the functional performance of the surfaces. In this present study, the motif analysis with 5% wolf pruning is applied to identify the significant hills for pattern reorganization of the surface texture generated by different finishing steps such as grinding, shape adaptive grinding (SAG) and chemical assisted SAG (CA-SAG). Several 3D advanced texture parameters are employed to characterize the coated surface before and after finishing in terms of surface roughness, third and fourth moments (skewness and kurtosis) of the probability density function, bearing area ratio curve and fluid retention properties of the surface. Furthermore, power spectral density (PSD) analysis is performed to analyse the unevenness and periodicity of the texture. It is observed that the fluid retention property and the bearing property of the surface improve with the subsequent finishing stage.