Comparative Study on Plasma Complex Treatment and Plasma Nitriding
SUN Fei 1 , LU Yangyang 2 , HU Jing 2
1. Changzhou Institute of Industry Technology, Changzhou 213164, China;
2. National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou 213164, China
Abstract：In order to take advantage of the individual advantages of plasma nitriding and plasma nitrocarburizing, and overcome their shortcomings, plasma complex treatment combining both plasma nitrocarburizing and plasma nitriding (hereinafter referred to as complex treatment) was developed and compared with a single plasma nitriding. The nitrided layer thickness, phase microstructure, cross-sectional microhardness were investigated by means of optical microscope, X–ray diffraction and microhardness tester. The results show that the compound layer thickness after complex treatment is much thicker than that after plasma nitriding, thus the nitriding efficiency is improved remarkably. Fe3C phase was occurred in compound layer after complex treatment, and the dominated phase of the compound layer was transformed from γ′ to ε phase. Higher microhardness was obtained after a complex treatment. In addition, activation energy (Q) of forming compound layer decreases from 179.7 kJ/mol in plasma nitriding to 87.1 kJ/mol for the complex treatment. And the kinetics of plasma nitriding and complex treatment in the temperature range of 783 K to 843 K was obtained as the following formula dplasma nitriding=exp（15.8–10810/T）, dcomplex treatment=exp（9.7–5237/T）.
2022, 
