Modeling and prediction on grinding force in ultrasonic assisted elliptical vibration grinding (UAEVG) of SiC ceramics using single diamond grain

In this study, a grinding force model suitable for ultrasonic assisted elliptical vibration grinding (UAEVG) was established on the base of kinematic characteristics, chip deformation mechanism and friction law. By analyzing the moving trajectories of single grain in pure elliptical vibration and UAEVG, two included angles between the resultant velocity and component velocity were deduced for the use of calculating the grinding forces. Three components have been taken into consideration in this model, such as the chip deformation force, the frictional forces on the grain flank and rake faces. Finally, the model was verified by grinding experiments of SiC ceramics with single diamond grain, and the unknown coefficients were computed and examined based on the experimental data obtained at different undeformed chip thickness and wheel speed. The grinding forces was increased with the increase of undeformed chip thickness but was wavelike with the increase of wheel speed. The predicted grinding forces were matched well with the experimental results, with an average error of about 15 % and a minimum error of about 2.2 %. The developed model could be theoretically applied to the prediction of grinding force under different working conditions by adjusting the unknown coefficients through preliminary experiments. In conventional grinding (CG), the grinding force increases with the increase of undeformed chip thickness, and the average errors of tangential force and normal force can be controlled within 16.8% and 8.5%, respectively.