Two-Stage Method of Cathode Electrolyte-Plasma Heating for Chemicothermal Treatment of Metal Materials

This work presents the results of studies on the features of the cathode electrolyte-plasma process. There were studied the current-voltage characteristics of cathode electrolyte-plasma process of treatment. The experiments were carried out with electrolytes from an aqueous solution containing 10% sodium carbonate and 15, 20, 25% urea. The current-voltage characteristics of the cathodic heating process were obtained in order to establish the possibility of controlling the electrolyte-plasma discharge and establish the boundaries of the working areas for PES.The current-voltage characteristics of the cathode process were obtained at various temperatures of the electrolyte and the active electrode (cathode). It was found that it is necessary either that the electrolyte be heated from 70 °C or the active electrode (cathode) is heated to 500 °Cin order to obtain a stable discharge at lower voltages. In order to obtain a stable discharge, the authors have developed an efficient two-stage cathodic heating mode, which allows for controlled cathodic plasma electrolytic saturation (PES) of steels. The method of two-stage electrolyte-plasma heating is the heating of the active electrode (cathode) to 400-500 0С with an abnormal discharge at voltages of 300-320 V, followed by a transition to film boiling mode by a sharp decrease in voltage to 180-200 V. The developed mode allows to obtain a stable discharge without the use of any additional operations on the same installation, which reduces the complexity of the process while increasing the productivity of the process.