Research on Gas Nitriding Technology Catalyzed by Rare Earth for 40CrNiMoA Alloy Steel

Abstract

A kind of gas nitriding method catalyzed by rare earth for 40CrNiMoA alloy steel was researched in this article. Effect of temperature on surface hardness of gas nitriding method catalyzed by rare earth, change law of layer depth with time at 500 °C were carried out and compared with normal gas nitriding. Based on these researches, gas nitriding method catalyzed by rare earth was optimized. The results show that gas nitriding catalyzed by rare earth can not only increase the nitriding speed, but also enhance the surface hardness of the nitriding layer. Using three - stage gas nitriding method catalyzed by rare earth and after 40 hours, the samples can meet the need of nitrided layer depth no less than 0.5mm, surface vickers hardness no less than 600.