Enhanced plasma nitriding assisted by combining hollow cathode discharge with rare earth oxide particles for iron-based metals

Abstract

Plasma nitriding (PN) assisted by combining hollow cathode discharge (HCD) with rare earth (RE) oxide particles was conducted on Cr12MoV steel. The HCD generated a high-density plasma and induced the release of RE elements from the RE oxide particles, thereby promoting the formation of more ε-Fe2-3N phases and the diffusion of more nitrogen into the surface layer. The hardness of the nitrided layer with the assistance of the combination of HCD with RE oxide particles was superior to that achieved by HCD-assisted PN and conventional PN.