Abstract: There is a swivel angle α between a grinding wheel and workpiece axes, which is named point grinding to be considered as a type of cylindrical grinding. The resulting grains path is changed because of α. To present its influence on workpiece surface roughness, the grains path is approximately described by a parabola using the kinematic relationship of the grinding wheel with the workpiece and coordinate transformation. Based on the hypothesis for the grinding wheel surface character, a geometrical workpiece micro-surface is generated through extending effective interaction trails. The workpiece of 45 harden steel is ground to test the proposed interaction model in typical grinding parameters. The simulation workpiece surface topologies display some similar features with the experimental results, and the distribution frequency of surface height is fitted with an average difference of 7.8% in cutting speeds tested. The surface roughness Ra tends to be approximately constant when the swivel angle changes from 0 to 4 degrees, and its waving range is less than 0.1 μm. This geometrical simulation method provides a supplementary and supervised method for analyzing the real topography.

Key words: Geometrical simulation, Grains path, Point grinding, Surface topology