Упрочнение поверхности титана модифицированием с применением электролитно-плазменного нагрева

Abstract

A new method is proposed for increasing the hardness, wear resistance and antifriction characteristics of the surface of titanium and titanium alloys, based on electrochemical-thermal treatment, which is performed by electrolytic-plasma heating in a nitrogen- or carbon-containing electrolyte, followed by hardening by turning off the operating voltage. When a voltage in the range of 100–300 V is applied to the electrochemical cell, local boiling of the liquid occurs around the workpiece due to the release of Joule heat. Under these conditions, the electrolyte near the surface of the workpiece is heated to the boiling point, and the workpiece being processed, being separated from the bulk of the electrolyte, is heated to temperatures of 400–1100 ºС. The high temperatures of the workpiece will make it possible to saturate the surface with atoms of light elements contained in donor substances dissolved in the electrolyte. The presence of carbon-containing and nitrogencontaining components in the electrolyte determines a certain carbon or nitrogen potential of the gasvapor shell, as a result of which chemical-thermal treatment becomes possible. Under the conditions of electrolytic-plasma heating, diffusion processes are intensified, which makes it possible to significantly reduce the time of chemical-thermal treatment to 5–10 min.