State of the Art on Ultrasonic Machining of Engineering Ceramics

Ultrasonic machining is a material removal process which does not depend on a conductive workpiece and is preferable for machining workpieces with low ductility and hardness above 40 HRC such as engineering ceramics etc. Material removal mechanism includes impacting, hammering and cavitations. Unlike other non-traditional processes such as laser beam machining, electrical discharge machining, etc., ultrasonic machining does not thermally damage the workpiece and it avoids the significant level of residual stresses which are important for the survival of brittle materials in service. In this paper, the fundamental principles of ultrasonic machining and its combinations with other processes, the material removal mechanisms and the effects of the operating parameters on material removal rate, tool wear rate are reviewed with emphasis on engineering ceramics.