Di Zhu

Investigation on Wire Electrochemical Micro Machining

Wire electrochemical micro machining (WEMM) using the online-fabricated micro wire electrode is proposed as a new method of micro machining. Based on electrochemical principle, the mechanism of nanosecond pulses WEMM was investigated. The hardware of the control system was founded using devices of virtual instruments, and the software of the system was designed based on Labwindows/CVI. The micrometer scale wire electrode was online fabricated, the diameter of wire electrode was real-time monitored by precisely measuring the variation in resistance of the electrode, and it is possible that accomplish the fabrication of wire electrode and the following processes continuously in the same machining system. The relations between the machining accuracy and parameters, such as velocity of feed forward and pulses parameters was experimentally studied, and a series of high-aspect-ration micro structure and multi-microgrooves were fabricated. The research of the paper sets up a firm foundation for application of the proposed wire electrochemical micro-machining.Copyright

Electrochemical Machining of Micro-Structures With Nanosecond Pulses

Electrochemical machining (ECM) is considered an advanced and promising technique due to several special advantages, such as non-contact machining without cutting force, no tool wear and heat-affected layer, etc. Base on the experimental results of micro-ECM, the influence of predominant process parameters, i.e. electrolyte concentration, pulse duration, period and voltage amplitude of power supply, on machining accuracy were investigated and discussed. Experimental showed that lower voltage amplitude and shorter pulse duration in micro-ECM process could produce more accurate micro structure shape. Using the self-developed experimental system, the micro tool-electrode and the complex micro-structures were sequentially machined. Upon the application of ultrashort voltage pulses, the letters with 20μm in line width were fabricated stably by the W tool electrode with 10μm diameter.© 2007 ASME