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应用ＴＧＡ、ＸＲＤ、ＳＥＭ／ＷＤＳ技术研究了Ｆｅ５０Ｍｏ合金在１ｋＰａ，７００～９００℃的硫蒸气中的高温硫化行为．发现在７００℃时硫化遵从抛物线规律，８００和９００℃时则变为线性规律．Ｆｅ５０Ｍｏ的硫化速度常数比纯Ｆｅ的低３～４个数量级，比Ｆｅ２０Ｍｏ和Ｆｅ４０Ｍｏ的抗硫化性能有了显著提高．热处理对合金硫化行为无显著影响．最初只出现ＦｅＳ单一硫化产物层，合金中发生μ相晶界处α－Ｆｅ相的选择硫化．长时间硫化后，ＦｅＳ层下出现ＭｏＳ２内层，其晶体片层垂直于样品表面，有助于扩散传质．但ＭｏＳ２层致密、微观缺陷少，因而有较好的保护性．
The high temperature vulcanization behavior of Fe50Mo alloy in 1kPa and 700 ~ 900 ℃ sulfur vapor was investigated by TGA, XRD and SEM / WDS techniques. It is found that the vulcanization follows the parabolic law at 700 ° C and becomes linear at 800 and 900 ° C. The vulcanization rate constant of Fe50Mo is 3 to 4 orders of magnitude lower than that of pure Fe, and the anti-sulfuration performance of Fe50Mo is significantly higher than that of Fe20Mo and Fe40Mo. The heat treatment had no significant effect on the vulcanization behavior of the alloy. Initially, only a single layer of the FeS single sulfidation occurred, and the selective sulfidation of the α-Fe phase at the μ-phase boundaries occurred in the alloy. After curing for a long time, the MoS2 inner layer appears under the FeS layer, and its crystal layer is perpendicular to the sample surface, which is conducive to diffusion mass transfer. However, the MoS2 layer is dense with few microscopic defects and therefore has better protection.