Research on factors affecting wear uniformity of the wheels in the double-sided lapping

Abstract

Uniform wear of lapping wheel helps to improve the surface accuracy of workpiece and increase the lifespan of wheel in double-sided lapping. The relative motion of workpiece has a significant effect on wear uniformity of the lapping wheel. In this paper, the wear uniformity of the wheel was studied from the perspective of the motion trajectory distribution of the workpiece relative to the wheel. We calculated the trajectory distributions on the wheel surface at different rotational speed ratios, workpiece placements and workpiece sizes. In addition, we used the variation coefficients of the standard deviation (VCSD) to evaluate the nonuniformity of the trajectory distribution. On this basis, a series of lapping experiments were executed to confirm the correlation between wear and trajectory distributions. With the rotational speed ratio as an example, the relationship between the wheel lifespan and the wear nonuniformity coefficient (VCSDΔh) is explained. The results show that when the rotational speed ratio was in a certain range, the farther the workpiece was placed from the carrier center and the larger the workpiece size, the better the wear uniformity and the longer the lifespan of the wheel. Thus, reasonable settings for parameters and configurations can prolong the lifespan of the lapping wheel.