Characteristic analysis of rotating ultrasonic machining applied in zirconia grinding

Abstract

This research uses rotary ultrasonic grinding technology to grind zirconia (ZrO2) ceramic. The purpose is the optimization of processing parameters for rough and fine grinding. According to Taguchi method, optimized processing parameters will be available to find and successfully verified. The objective function of rough grinding is the material removal rate (MRR), and a maximum is expected. The processing parameters can be spindle speed, ultrasonic power, feedrate, and cutting depth. The best MRR is 192mm3/s in Taguchi’s experiment, and the optimized MRR is 2.14mm3/s, which can be increased by 1.11 times.Moreover, the objective function of fine grinding is surface roughness (Ra), which needs to find a minimum value. The control factors are spindle speed, ultrasonic power, feedrate, and the number of times of grinding. In the Taguchi experiment, the minimum roughness predicted by the fine grinding is Ra0.16, but the roughness is obtained Ra0.2 by the verification experiment. It may be that the effects of the factors are not completely independent, and there are interactions between them. The predicted value will not be completely correct via the superposition of each factor effect. It can also be found that the independence of the fine grinding speed, ultrasonic power and feed factor is not strong enough for the variation analysis. It affects the results of the prediction and confirmation experiment.