Influence of Micro-Texture on the Tribological Behavior of WC/MoS2/Fe-Based Alloy Coating by Laser Cladding

Abstract

In order to combine the anti-friction performance of micro-texture with the lubrication effect of solid self-lubricating phase, and further improve the tribological performance of the coating under dry friction conditions. Fe₅/10%WC/5% MoS₂ self-lubricating coating was prepared by laser cladding technology, and then elliptical micro-textures with different arrangement angles (0°, 45°, 90°) were processed on the surface of the coating by laser micro-texture technology. The friction and wear behavior of the micro-texture coating was investigated from the perspectives of friction coefficient, volume wear loss, and wear morphology. The improvement effect of micro-texture on the wear resistance of the coating was discussed, and the synergistic anti-friction mechanism of the self-lubricating coating and surface micro-texture was explored. The results show that the friction coefficient and volume loss of the 0° textured coating are the smallest under the external load of 70 N, and the wear mechanism is characterized by slight abrasive wear. The 45° textured coating exhibits local adhesive traces in addition to a few micro-cutting furrows, suggesting a combination of slight abrasive wear and adhesive wear. The friction coefficient and volume loss of the 90° textured coating are the largest and the volume loss is greater than that of the non-textured coating. The wear mechanism is dominated by fatigue wear, accompanied by slight abrasive wear and adhesive wear. During the friction and wear process, the elliptical micro-pits can promptly capture wear debris, reducing the continuous damage to the coating. Additionally, the solid lubricant (MoS₂) stored in the micro-pits can provide continuous lubrication to the friction contact area and effectively decrease the friction coefficient.