Servo Scanning EDM for 3D Micro Structures

Abstract

In electro discharge machining (EDM) for 3D micro structures, the electrode wear is serious and it needs to be compensated in process. To obtain a better balance of the machining accuracy and efficiency, a servo scanning EDM method is proposed for 3D micro structures, in which the electrode wear is compensated on real-time by controlling the discharge gap constant. It is supposed reasonably that the machining depth of each layer in servo scanning EDM is consistent if discharge gap is kept preferably. The servo scanning EDM strategies include the model design by Pro/Engineer (Pro/E), the plan and simulation of scanning path, and the machining process. The 3D micro structures are machined by scanning layer-by-layer under servo control of the electrode with monitoring discharge gap signal. The CAM, gap servo control, and real-time electrode wear compensating are integrated into the machining system. The evaluation experiments of servo scanning EDM and the typical machining experiments of 3D micro structures have been carried out. The machining results show that the electro discharge in the servo scanning EDM is more stable. Servo scanning micro EDM is propitious to improve machining accuracy and efficiency in 3D micro structures.