Study of sudden tool failure in micro electro discharge milling

Micro electro discharge milling (MED milling) is a spark erosion method capable of micromachining prismatic and complex shapes using simple non-profiled tool. Tool wear poses major hurdle in the development of MED milling. This paper discusses the types of tool wear in MED milling and analyses factors causing exfoliation and sudden failure of micro tool. Process simulation of MED milling suggests using less viscous dielectric fluid, lower tool rotational speed and higher discharge gap to reduce the chances of unpredictable tool failure in MED milling.