Kinetics comparison between plasma oxynitriding and plasma nitriding and the application for AISI 1045 steel

Plasma oxynitriding (PON) and plasma nitriding (PN) were carried out for AISI 1045 steel, and kinetics of the two cases were analysed and compared. Kinetics equations of [Formula: see text] and [Formula: see text] were obtained for PON and PN, respectively, which illustrates that much higher nitrogen diffusion coefficient and much lower activation energy for PON. Meanwhile, the reliability of obtained kinetics equations were verified by checking the agreement between the calculated compound layer thickness and those measured from the cross-sectional microstructures. The results confirmed the practicability of the kinetics equations.