Abstract: New swing plane lapping method with irrational speed ratio is proposed based on the certain eccentric plane lapping method. Kinematic analysis of swing plane lapping is established by vector method. Trajectory of abrasive particles and the distribution of velocity field on the workpiece surface driven by fixed eccentricity and swinging are simulated, then uniformity of the density of motion trajectory and material removal rate are evaluated by micro unit and statistical methods. Results show that the trajectory of the swinging plane lapping is more complex, and the area covered by abrasive particles is larger. There is no obvious Newton ring phenomenon under irrational speed ratio, and more uniform trajectory distribution can be obtained faster. Uniformity of the trajectory is significantly improved by using the irrational speed. Distribution pattern of abrasive velocity field under the two driving modes is the same under the same speed ratio. There is no obvious period when the velocity and velocity direction angle of single abrasive was changed under the swing mode, and the speed obtained is faster than that under the certain eccentricity type, and material removal can be achieved faster and more uniformity under the irrational speed ratio. Finally, the experimental platform of two driving methods was built for the comparative lapping experiment. The surface roughness Ra of the silicon chip obtained by the irrational swinging Lapping method is the lowest, and the material removal is the largest within the same time.

Key words: kinematic analysis, lapping uniformity, eccentricity, velocity field, material removal