Plasma nitriding is an economical method to improve the hardness as well as fatigue and wear resistance of ferrous and nonferrous materials. It can be performed either at high or low pressure. Plasma cutting is carried out in a water-cooled evacuated chamber. Chamber surface forms the anode while work-pieces inside are connected to negative terminal. Design of the fixture containing large number of specimens should be such that there are enough gaps amongst them in order to avoid hollow cathode formation. Glow discharge region of nitrogen containing plasma is used for nitriding. Nitrogen ions in the plasma stream striking the clean cathodic substrate promote not only nitriding the surface but also provide the heat necessary for the diffusion process.