A holistic approach for zero-defect micro-EDM milling

Micro-EDM (μEDM) milling is a well-established micro-manufacturing technique, which offers three-dimensional and flexible machining capabilities for structuring electrically conductive difficult-to-machine materials. There has been considerable progress in micro-manufacturing capabilities by μEDM in recent years. Nevertheless there still exist a few challenges in terms of process accuracy and efficiency, and the achievable shape accuracy in micro-EDM milling is limited to 3-4 microns in vertical direction and 2-3 microns in plane. In order to reach zero-defect manufacturing with this micro-sparking technique, a holistic approach for precision micro-EDM milling is pursued at Leuven University. To improve the overall performance of the micro-EDM milling process, various upgrading has been carried out on a SARIX^® machine, which includes monitoring and controlling of the stability of the sparking process (gap variation and energy distribution etc.), wear compensation of the tool-electrode, and on-machine metrology. Preliminary experiments have been carried out with promising results, and further system integration and application on industrial demonstrators are in progress.