Tribological mechanism of micro/meso/macroscopic textured surfaces under different normal forces, relative velocities, and sliding directions

Friction behavior under different operating conditions, such as normal forces, relative velocities, and length scales of the textured surfaces, is a crucial topic in tribology. In this study, different tribology mechanisms of micro/meso/macroscopic textured surfaces were investigated, considering the effects of asperities and operating conditions. A prediction model of the friction coefficient was proposed and validated for polished and microscopic, mesoscopic, and macroscopic textured surfaces. Subsequently, reciprocating sliding friction experiments (sphere-on-plate) were carried out to estimate the friction coefficients of the specimens in contact with an aluminum sphere (Al 99.9). The results indicate that a larger normal force, relative velocity, and length scale produce more wear debris, which transforms the friction mode from adhesive friction to abrasive friction.