The diffusion behavior and surface properties of catalytic nitriding with LaFeO3 film prepared by the sol-gel method

In the present work, LaFeO3 film prepared by the sol-gel method was applied to realize the catalytic plasma nitriding for 38CrMoAl steel. The plasma nitriding treatments were conducted at 520 degrees C for 4, 8 and 12 h. The plasma nitriding without LaFeO3 film was set as a normal group. The microstructure, phase structure, mechanical and tribological properties of the plasma nitrided layers with and without the LaFeO3 film were investigated in comparison. The LaFeO3 was proved to be effective for accelerating plasma nitriding because it suppresses the formation of the compound phase and layer. Moreover, the LaFeO3 has a positive effect on the surface mechanical and tribological properties. Interestingly, the effect mechanism was varied during the nitriding process, which was discussed based on the experimental results.