Ultrasonic machining

Abstract

A major effort is underway to develop new and enhanced ceramics, semiconductors and superconductors for components requiring higher accuracy, better surface finish, lower degrees of surface degradation and more complex geometry than ever before. Typical methods for machining ceramics have had limited success primarily because of the resultant surface imperfections. Ultrasonic machining (USM) uses a nonabrasive form tool, vibrating at ultrasonic frequencies, to excite fine abrasive particles flowing in the machining gap, causing uniform stock removal. The process is especially suited to machining complex three-dimensional shapes, up to 100 mm (4 inches) in diameter, in brittle materials. The ultrasonic machining process has a number of important advanatages for ceramic applications: conductive and nonconductive materials can be machined, material hardness is relatively unimportant, there are no chemical or electrical alterations on the workpiece surface and complex three-dimensional contours can be manufactured as quickly as simple ones.