An Investigation of the Differences Between NaCl and NaClO[sub 3] as Electrolytes in Electrochemical Machining

Abstract

Constant potential polarization curves were obtained on steel rotating disk anodes in concentrated and electrolytes, and steady‐state polarization curves were obtained on stationary soft iron anodes in , , , and solutions. The results show that the metal removal reaction is activation controlled and that electrolytes are reduced to with extended periods of electrochemical machining. Tests conducted in a flow system showed that up to 50 g/l of could be tolerated in a concentrated electrolyte (350 g/l) before the excellent machining properties of the electrolyte become impaired. Wild cutting electrolytes do not form protective films on ferrous metals, whereas noncutting electrolytes form too highly protecting films of . The good dimensional control is obtained with electrolytes which behave in an intermediate way and possess a sharp transition from the passive to the transpassive state.