Micro-punching process of stainless steel foil with micro-die fabricated by micro-EDM

Micro-punching has become a potential micro-manufacturing process due to the simplicity of the process, low cost, high production capability and accuracy. But the size of a punched micro-hole is limited due to the difficulties of tool fabrication. In the paper, we propose a design procedure according to buckling theory and a kind of micro-die fabrication method for micro-punching process. Micro-punch and female die with high dimensional accuracy were fabricated by micro-EDM with block electrode. Micro-punching processes of stainless steel foil were conducted with the micro-punch and female die equipped in the precision micro-punching tool. Micro-holes of 300, 150 and 100 μm in diameter were pierced with a good profile and high dimensional accuracy, which indicate that the micro-die fabricated by micro-EDM is suitable for micro-punching processes.