Nb 对氢在 Fe-13Cr-6Al-2Mo 合金中扩散行为的作用

采用电化学氢渗透方法研究氢原子在 Fe-13Cr-6Al-2Mo 和 Fe-13Cr-6Al-2Mo-0.5Nb 合金中的扩散行为, 分析了 0.5%Nb(质量分数, 下同)对氢原子在 Fe-13Cr-6Al-2Mo 合金中扩散行为的作用. 研究结果表明: 当在 Fe-13Cr-6Al-2Mo 合金中添加 0.5%Nb 后, 合金的晶粒得到细化, 同时合金中析出大量弥散分布的细小 Fe$_{2}$Nb 相. 0.5%Nb 的添加大幅度降低了氢原子在 Fe-13Cr-6Al-2Mo 合金中的表观扩散系数, 使氢原子在合金中的扩散激活能提高了 50.3%. Nb 原子通过提高合金中的氢陷阱浓度, 有效降低了氢原子在 FeCrAlMo 基合金中的扩散速率.

Effects of Nb on hydrogen diffusion in Fe-13Cr-6Al-2Mo alloys

In this study, the diffusion behaviors of hydrogen atoms in Fe-13Cr-6Al-2Mo and Fe-13Cr-6Al-2Mo-0.5Nb alloys were studied by the electrochemical hydrogen permeation method. The effects of 0.5% Nb (mass fraction) added to the alloy on the diffusion behavior of hydrogen atoms in the Fe-13Cr-6Al-2Mo alloy were analyzed. Results showed that the grain of the alloy was refined, and a large amount of fine Fe$_2$Nb phase was dispersed in the Fe-13Cr-6Al-2Mo alloy when 0.5% Nb was added. The results also showed that 0.5% Nb greatly reduced the apparent diffusion coefficient of hydrogen in the Fe-13Cr-6Al-2Mo alloy and increased the diffusion activation energy of hydrogen in the alloy by 50.3%. The Nb atom effectively reduced the diffusion rate of hydrogen in the FeCrAlMo-based alloy by increasing the hydrogen trap concentration in the alloy.