The surface roughness during electro-contact-electrochemical machining with vibration of a cathode-tool

Electrical discharge machining and electrochemical machining of metals are used in the production of parts for aircraft and rocket technology, especially electrical discharge machining. A type of electrical discharge machining, electrical contact machining, is used in metallurgy. The paper investigates a combined method of metal machining, including electrical contact and electrochemical methods using vibration of the electrode tool. This method is used for copying and piercing operations in the manufacture of parts from metals that are difficult to machine mechanically. The peculiarity of the above-mentioned method of electrical machining is the formation of surface roughness of the metal being machined due to anodic dissolution and the electrical discharge machining process. The side surface of the workpiece is formed due to electrochemical processes. The end surface is formed due to electrical contact machining. Based on literature data for pulsed electrochemical machining and experiments, expressions for calculating the roughness parameter of the side surface are obtained. The formula takes into account the time of anodic dissolution for one period of oscillation of the cathode tool, the voltage on the electrodes and the concentration of the electrolyte. The calculation of the roughness parameter of the end surface is carried out similarly to the expression for electrical discharge machining, but instead of the duration of the electric pulse, the duration of contact of the electrodes is used. The experiments carried out confirmed the correctness of the expressions used and made it possible to obtain the dependence of the coefficient on the vibration frequency of the cathode-tool.