Generation mechanism and anti-friction effect evaluation of continuous micro-groove texture machined by ball-end milling process

Abstract Based on ball-end milling cutter characteristics, it takes advantage of the flexibility and controllability of its tool path during processing. The aim of this research is to process continuous microgroove textured surfaces by using ball-end milling cutters. Evaluation of the anti-friction effect of continuous microgroove texture by combining simulation and friction tests. The results indicate that, the surface topography of continuous microgrooves can be obtained by combining small feed per tooth and large radial cutting depth. The radial depth of cut and tool radius affect aspect ratio of microgrooves. The bearing capacity of the oil film shows an increasing and then decreasing trend with the increase of radial depth of cut and orientation angle. The radial depth of cut increased from 0.1 mm to 0.3 mm, resulting in a maximum 4.87% increase in the bearing capacity of oil film because of the enhanced wedge effect. However, further increase in radial depth of cut leads to increased vortex, weakening the wedge effect. The oil film bearing capacity is reduced so that the friction coefficient increases by a maximum of 510%. Moreover, as the orientation angle increases from 10° to 20°, the bearing capacity of the oil film increases by 22.7%. The minimum friction coefficient currently is 0.0215. However, when the microgroove orientation angle is further increased, the countercurrent effect is enhanced and the dynamic pressure effect is weakened, which finally leads to a decrease in the bearing capacity of the oil film. The friction coefficient has increased by 30.2% maximum. This study is of great significance which provides a new method for guiding the friction reduction on the die surface.