Tribological performance of textured WC coatings under silt-laden water with different filtration precisions

Abstract

Suspended silt particles in natural water inevitably enter open water hydraulic systems, challenging the tribological performance of materials and complicating the selection of appropriate system filtration precision. This study aims to investigate the tribological performance of textured surfaces and the mechanisms of particle contamination resistance under different filtration precisions. Purified water was used as a control, while silt water with an initial mass concentration of 1 % was filtered through 100 μm, 40 μm, and 10 μm filters as experimental groups. The friction and wear performance of HVOF-sprayed WC-9Co-5Cr-1Ni coatings, both textured and untextured, paired with untextured Si₃N₄, was evaluated under these lubrication conditions. Results showed that texturing reduced the friction coefficients significantly. In silt-laden environments, textures not only stored particles but also facilitated their fragmentation or layered delamination through interactions with texture edges. Compared to untextured surfaces, textured surfaces reduced the filtration precision requirement from 10 μm to 40 μm without significant material damage and facilitated lubricating film formation in silt-laden environments. These findings may provide guidance for texture design in tribopairs and filtration strategies in silt-contaminated hydraulic systems.