Use of the Vacuum Arc Discharge for the Surface Modification

Abstract

AbstractSteel surface saturation by nitrogen (nitriding) results in a high increase in surface hardness and a decrease in friction rate. This treatment is widely used to increase the lifetime of cutting tools and wearing parts in machines.A new approach of steel surface treatment by using the vacuum arc discharge in nitrogen is presented. The apparatus uses two arc vacuum discharges. The first discharge is a metal vapor discharge and serves for both the cleaning- heating of the treated surface and for the initiation of the second vacuum arc discharge in nitrogen. The vacuum arc source of metallic plasma allows us the simultaneous implantation of desirable metals and surface saturation by nitrogen. The developed arc vacuum discharge method shortens the nitriding time 2 to 3 times in comparison to the glow discharge technology. The suggested method of the surface treatment is suitable for a wide variety of steels. The hardness measurement results of nitriding and combined chromium with nitriding treatments of several steel samples are presented and discussed.