Effects of High Frequency Vibration on the Surface Quality in Rotary Ultrasonic Machining of Glass BK7

Abstract

Both rotary ultrasonic machining (RUM) and conventional grinding (CG) experiments were performed on the glass BK7 specimen to investigate the effects of high frequency vibration on the surface quality. The surface morphologies produced in the two machining processes were assessed and the associated material removal mechanisms were explored. Also, the influence of the spindle speed on the surface roughness was discussed. It was found that the mechanisms of the material removal involved in the RUM process were material pulverization and brittle fracture, while ductile flow and brittle fracture prevailed on the material removal in CG process. The increased spindle speed would reduce the lateral cutting depth of each abrasive, and promote the shielding effects of the lateral cracks generated by the previous abrasive, leading to the reduction of the surface roughness in both RUM and CG processes.