Mechanism and Experiment Study of Non-Contact Ultrasonic Assisted Grinding

Abstract

Ultrasonic-assisted grinding processing can effectively reduce the surface roughness and enhance the processing efficiency in the processing of hard and brittle materials. However, the most common ultrasonic assisted grinding is a type of contact ultrasonic grinding where the grinding tool directly contacts the workpiece, which means that it is necessary to accurately control the pre-pressure of the grinding tool on the workpiece. The control of pre-pressure will inevitably increase the complexity of the grinding device, and it is easy to wear the workpiece because of improper pre-pressure control. In this paper, a non-contact ultrasonic grinding method is proposed and the machining mechanism of non-contact ultrasonic grinding is revealed. The resonant frequency of the ultrasonic vibration system and vibration amplitude of the grinding tool working face were simulated and experimentally tested, respectively. Then, the experiment of non-contact ultrasonic grinding of a sapphire wafer was carried out. The result showed that non-contact ultrasonic grinding of the sapphire wafer could reduce the surface roughness by 48.6%. Compared with traditional contact grinding of sapphire wafer under certain pre-pressure conditions, the experimental results show that non-contact ultrasonic grinding has better effects in reducing surface roughness, improving processing efficiency, and improving the quality uniformity of the workpiece machining surface.