为了探究SKD11钢的优化氮碳共渗工艺，对SKD11钢在530 ℃不同共渗时间、不同炉内气压、NH₃/CO₂不同气氛比值情况下的离子氮碳共渗进行了研究。运用XRD、SEM、显微硬度、摩擦磨损试验，对材料的显微组织、显微硬度和耐磨性进行了分析。试验结果表明：对于冷作模具钢SKD11，时间为10 h、NH₃/CO₂为10∶1、炉内气压为500~700 Pa时，氮碳共渗效果相对最好。另外，在上述优化工艺基础上，随着稀土La的加入，渗层变厚且渗层与基体结合更致密，表层到心部的硬度梯度更小，氮碳共渗效果更好。

To obtain the optimal nitrocarburizing parameters for SKD11 steel, their specimens have been plasma nitrocarburized at 530 ℃ for different times in a mixed gas of NH₃ and CO₂ with and without rare earth (RE). The microstructure, microhardness, and wear resistance of surface layers for the treated specimens were characterized using scanning electron microscopy (SEM), Xray diffraction (XRD), and microhardness and wear testers, respectively. Results show that for SKD11, the optimal parameters for plasma nitrocarburizing treatment are the time of 10 h, NH₃to-CO₂ ratio of 10∶1, and air pressure in the furnace of 500-700 Pa. Based on the optimal parameters, when adding lanthanum, the nitrocarburized layer becomes thicker and more compact, the gradient of hardness gets smaller from the surface to the core, and the results of plasma nitrocarburizing treatment is better.