Duplex treatments of plasma nitrocarburizing and post-oxidation in an adiabatic plasma furnace

The duplex treatments of plasma nitrocarburizing plus post-oxidation have been carried out in a self-made adiabatic plasma furnace. The sample material is medium carbon steel AISI 1045. The compound layers are made up of Fe3O4 oxide layer, Fe2–3N compound layer and Fe4N diffusion layer. The compound layers exhibit excellent wear-resisting and corrosion-resisting properties. The properties are attributed to high hardness of the Fe2–3N compound layer, low friction coefficient and high chemical stability of the Fe3O4 oxide layer. Experiment shows that the duplex treatments carried out in the adiabatic plasma furnace are an environment-friendly process.