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稀土碳氮共渗与常规气体渗碳或碳氮共渗相比,它可提高渗速22～27％,提高有效硬化层深度21～27％。降低了共渗温度,缩短了生产周期,每炉可节省时间20％,其节能效果非常显著。稀土碳氮共渗提高了渗碳氮浓度,改善了钢的组织,使碳氮化合物弥散均匀分布。稀土在碳氮共渗中改善了钢的力学性能;使20CrMnTi钢表层显微硬度从未加稀土时的HV800提高到HV1000以上,冲击韧性提高27％。新工艺能减小齿轮花键孔变形,保证公法线尺寸的稳定性,显著减小了锥齿轮的平面翘曲度,提高了产品质量。使齿轮合格率从过去的85～90％提高到99％,获得了较好的社会经济效益,是化学热处理的发展方向之一。
Rare earth carbonitriding compared with conventional gas carburizing or carbonitriding, it can increase the penetration rate of 22 to 27%, improve the depth of the effective hardened layer 21 ~ 27%. Reduce the co-infiltration temperature, shorten the production cycle, each furnace can save 20% of time, its energy-saving effect is very significant. Rare earth carbonitriding increases the carburizing nitrogen concentration, improves the microstructure of the steel, and disperses the carbonitrides evenly. Rare earth in carbonitriding improve the mechanical properties of steel; 20CrMnTi steel surface microhardness increased from no HV800 HV800 above, impact toughness increased by 27%. The new process can reduce the gear spline hole deformation, to ensure the stability of the common normal size, significantly reducing the plane bevel gear warpage, improve product quality. So that the gear pass rate from the previous 85 ~ 90% to 99%, access to a better social and economic benefits, is one of the development direction of chemical heat treatment.