Application of Surface Discharge for Plasma Nitriding Technique

Abstract

In this study, we propose a new application of the technique for plasma nitriding of steel. The polarity of the applied voltage to a plasma gun was found to significantly affect the plasma formation. When the positive voltage was applied, a relatively large chamber was filled with the nitrogen plasma. The length of insulating capillary tube also affected the emission intensity of nitrogen ion in the plasma. Nitriding experiments of high speed steel showed a considerable improvement of the hardness without forming so-called “white layer (Fe_2-3N)” or damage on the surface. It can be concluded that this technique can be one of the most superior techniques for nitriding steel.