Effect of process temperature on the microstructure and properties of gas oxynitrocarburized 35CrMo alloy steel

摘要

In the present investigation, 35CrMo alloy steel was gas oxynitrocarburized at 550 ℃, 570 ℃ and 610 ℃ for 2 h by applying a low-temperature gas multi-elements penetrating system. Microstructure, surface composition, case depth, microhardness, wear and corrosion resistance were analyzed. The compound layer consisting of γ'-Fe_4N and ε-Fe_3N and oxide layer of Fe_3O_4 and Fe_2O_3 were formed on the ground reference surface after treated. Compared with the conventional gas nitrocarburizing, a larger effective case depth was obtained successfully in a short time after treatment. The microhardness and the properties of wear and corrosion resistance were improved obviously and the properties of samples treated at 570 ℃ are optimum when compared with the samples treated at 550 ℃ and 610 ℃ for the same duration.