Ultrasonic machining (USM) technique has long been used for fabricating various patterns and drilling holes on brittle materials. However, the surfaces generated by USM are normally rather rough and covered by deep penetrated cracks. This has greatly limited USM being used in micro-machining and fine machining. This research aimed to study the surface integrity of the USMed surface and develop a feasible way to minimize the scattered cracks so that good surface finish could be achieved. Machining parameters such as type and concentration of abrasive particles, grit size, and feed rate were systematically investigated to check their influences on the surface obtained. A ‘multi-stage’ micro-USM process was developed in this study and surface with Ra value better than 0.2m was achieved using the proposed process.
