Ultrasonic-Vibration-Assisted Micromachining of Sapphire

Abstract

Sapphire is an attractive engineering material for the cover glass of smartphones and wristwatches because of its high hardness and resistance to corrosion, wear, and heat. However, the high rate of tool wear and brittle chippings around the holes are serious problems associated with drilling sapphire. To enhance the accuracy and efficiency of the drilling process on sapphire, this paper presents a novel tool-path strategy using helical milling along with various tool path patterns. Experimental results show that the proposed method successfully reduces brittle chippings around the holes.