Effect of squamous textured SiC on the dry-sliding tribological properties of graphite asperities

Abstract

The graphite rough morphology influences the operating performance of the sealing surface. Texturing silicon carbide surfaces can considerably improve the tribological characteristics of sealing surface. Herein, a fractal model was established to study the contact and tribological characteristics of graphite asperities, and the pin-on-disk wear tests were conducted to investigate the influence of squamous texture on graphite asperities under dry-sliding condition. Results indicated that reducing the graphite surface roughness decreases the contact area to decrease the friction coefficient. The squamous texture increases the deformation and contact area of graphite asperities. But the wear debris collection of the squamous texture prevents the adhesive wear, and the microcutting effect promotes the formation of graphite transfer film on the silicon carbide surface. Therefore, the squamous texture has the low friction coefficient and excellent worn morphology. Especially, under the high load of 80 N, combining the textured silicon carbide with the optimal graphite surface roughness of 0.14 μm exhibits a synergistic anti-friction effect that the friction coefficient reduced by 19%.