An Overview of Research Attempts on Micro Electro Machining at Tsinghua University

摘要

Electro discharge machining (EDM) process is considered suitable to micro machining. Micro EDM is an inexpensive, simple and convenient micro machining approach. And it is also a feasible way to produce microstructures with 3 dimensions and high aspect ratio on metal alloy materials. Based on such viewpoints, we started fundamental research on micro EDM techniques in our initial period. A micro EDM prototype with a piezoelectric inchworm mechanism for micro feed was developed and some machining experiments were carried out. Then our research focus was once shifted onto possible industrial applications to utilize micro EDM technologies. An inchworm mechanism for continuous feed of thin wire electrode was developed and a micro EDM drill was constructed specially for drilling fuel jet nozzles. Further, a servo scanning EDM method for 3D micro structures was proposed in which electrode wear is compensated on real time by servo control of discharge gap.