Micro-dimple and micro-bulge textures:Influence of surface topography types on stick-slip behavior under starved lubrication

Stick-slip behavior, a common problem of contact under severe lubrication, is closely related with surface topography. To investigate the influence of surface topography types on stick-slip behavior, micro-dimple and micro-bulge textures, typical concave and convex topographies, were fabricated by pulse picosecond laser and CW fiber, respectively. A gyroscope sensor was mounted on the pin-on-disc modular of multifunctional tribometer to conduct friction dynamics tests. The intensity of stick-slip behavior is characterized by the amplitude and duration of stick-slip behavior. The results show that, under the same starved lubrication, the micro-bulge textured disc showed the lowest intensity while the untextured one showed the highest intensity. In comparison with micro-dimple and micro-bulge textured disc exhibits higher efficiency in inhibiting stick-slip behavior as well as starting stable sliding. The mechanism of inhibiting stick-slip behavior for micro-dimple textures is generated by trapping wear debris and forming effective oil film. However, the cause of micro-bulge textures is the reduced contact area, which result in the reduction of the propensity of secondary plateaus, plastic flow, and adhesive junctions between asperities.