In‐situ investigation of the surface‐topography during anodic dissolution of copper under near‐ECM conditions

Electrochemical machining is characterized by deliberate high speed anodic dissolution. The distance between anode and cathode are only a few hundred microns. Additionally, the electrolyte flow rate is in the range of approximately meter/second. A special electrochemical cell design was developed to investigate the surface topography during the anodic dissolution simultaneously and in‐situ under near‐ECM conditions. The anode was directly placed under the cathode with a gap of 350 µm. We carried out pulse experiments at 15 A/cm 2 and 25 A/cm 2 with an electrolyte flow rate of 4m/s. First‐time it was possible to observe the surface changing of the anode directly during current pulses by using a video camera. Different stages e.g. roughening, film formation or gas evolution could be distinguished.