Distribution of Temperature Zones during Electrolytic Plasma Heating of Titanium Alloys

. Electrolytic-plasma treatment (EPT) is a promising method for improving the operating characteristics of metal materials. Anodic electrolytic-plasma hardening is a variation of EPT. This technology makes it possible to saturate the surface of the processed parts with atoms of light non-metallic elements, included in the composition of the electrolyte used. Limitations to the widespread use of electrolytic-plasma hardening in industry are associated with a number of process features, expressed in the uneven heating of the workpieces, as well as the need for them to be slowly immersed into the electrolyte to avoid disruption of the heating process. The paper presents the results of a study of the influence of operating voltage on the maximum heating temperature and the distribution of temperature zones during electrolytic-plasma heating of cylindrical samples made of VT6 titanium alloy. It has been established that electrolytic-plasma treatment in an ammonium chloride solution at an operating voltage of 200 to 260 V ensures heating of samples to a temperature of 1200 °С. The highest heating temperature is observed at a voltage of 260 V, and the lowest at 200 V. At the same time, samples undergoing processing are characterized by the presence of a temperature gradient along the height (maximum heating is observed in the most submerged part of the sample). During the EPT process, up to six distinct temperature zones are identified , but no more than five such zones exist simultaneously. Reducing the length and diameter of the samples leads to their more uniform heating. In this case, the size of the zones with the highest temperature increases due to the reduction or disappearance of the least low temperature zones. The opposite pattern is observed with increasing sample length.