摘要
用ＴＧＡ、ＸＲＤ、ＳＥＭ观察分析了Ｆｅ５０Ｍｏ合金在９００℃、１０～５０ｋＰａ的硫蒸气中的高温硫化动力学曲线和硫化产物层的组成及结构。发现硫化动力学基本不受硫压的影响，但高硫压下合金发生较严重的硫化，其产物层由低硫压时的一、二层变为类似于Ｆｅ４０Ｍｏ产物层的三层结构：外层ＦｅＳ／中间层ＭｏＳ２／内层Ｆｅ、Ｍｏ的复杂硫化物。内层虽然在硫化后期生成，但发展速度比中间层快，密度也较低。中间层是阻止合金进一步硫化的主要产物，但仍允许Ｆｅ２＋通过，使外层ＦｅＳ得以继续生长，合金进一步硫化。
The sulfidation behavior, including kinetics and scale structure, of Fe50Mo alloy at 900℃ in sulphur vapour of different pressures was observed with TGA, XRD and SEM. No significant effect was found about the sulphur pressure change on the sulfidation kinetics, although severe sulfidation happened at higher sulphur pressure. A triplex scale at high sulphur pressure, consisting of outer FeS, middle MoS 2 and an inner complicated sulfide, substituted the single or duplex scale at lower sulphur pressure. The inner layer showed a faster thickening rate and a lower density comparing with the former formed middle layer. The middle layer behaved as the main product to resist further sulfidation. But its structure and crystal orientation allowed the pass of Fe 2+ ions through this layer, and therefore the alloy could be sulfidized continously.
基金
国家自然科学基金
