Research on oxidation behavior of end face of tool electrode in electrochemical machining of small deep hole

In the deep hole electrochemical machining of tubular electrode, the main reason of short circuit is oxidation film layer on the end face of electrode. The morphology and composition of the tool electrode end face processed by unidirectional pulse and bidirectional pulse are analyzed using scanning electron microscopy (SEM), and the formation mechanism of oxide film layer is also analyzed. The results show that the continuous loose oxidation film layer is formed on the end face of tubular electrode by using unidirectional pulse, its compositions are mainly the oxides of C and Si, the main reason of forming oxide film layer is the adsorption effect of tool electrode, using the right proportion of positive and negative pulse can inhibit the forming of oxidation film and the formed oxidation film layer could be removed efficiently, and the stability of electrochemical machining deep holes can be improved apparently.