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研究了在脉冲等离子体稀土渗氮过程中稀土元素Ｌａ对氮浓度分布和相结构的影响，揭示了Ｌａ在化合物层中的扩散规律．结果表明：与常规离子渗氮相比，稀土元素的添加，提高了表面氮浓度，随处理时间的延长而增加；当渗氮时间从２ｈ增加至２４ｈ时，化合物层由单相ε－Ｆｅ２－３Ｎ（ε）转化为ε－Ｆｅ２－３Ｎ和γ－Ｆｅ４Ｎ（γ’）双相．此外，Ｌａ可以扩散进入ε和γ’相中．Ｌａ的扩散规律受制于化合物层中γ’－Ｆｅ４Ｎ的比例．随时间延长，化合物层中γ－Ｆｅ４Ｎ的比例增加，Ｌａ的扩散加快，且在２—２４ｈ范围内其扩散遵循指数规律。
The effect of rare earth element La on the nitrogen concentration distribution and phase structure in pulsed plasma nitriding was studied, and the diffusion rule of La in the compound layer was revealed. The results show that the addition of rare earth elements increases the surface nitrogen concentration and increases with the increase of treatment time. Compared with conventional nitriding, the compound layer increases with the increase of treatment time. When the nitriding time increases from 2h to 24h, 3N (ε) into ε-Fe2-3N and γ-Fe4N (γ ’) biphasic. In addition, La diffuses into the ε and γ ’phases. The diffusion law of La is governed by the ratio of γ’-Fe4N in the compound layer. With the extension of time, the proportion of γ-Fe4N in the compound layer increases, and the diffusion of La accelerates, and its diffusion follows the exponential law in the range of 2-24h.