In ultrasonic machining tool is made of

Concept:

Ultrasonic machining is an operation that involves a vibrating tool fluctuating at the ultrasonic frequencies to remove the material from the workpiece. The process involves an abrasive slurry that runs between the tool and the workpiece.

It is typically used on brittle materials as well as materials with a high hardness due to microcracking mechanics.

Tools should be constructed from relatively ductile materials. The harder the tool material, the faster its wear rate will be. Thus the tools are made of tough, strong, and ductile materials like soft steel, brass or copper, and other ductile metallic alloys.