Fe40Mo合金在1kPa硫蒸气中的高温硫化

Sulfidation of Fe40Mo in 1kPa Sulphur Vapour 

用ＴＧＡ、ＸＲＤ、ＳＥＭ／ＷＤＳ对Ｆｅ４０Ｍｏ合金在１ｋＰａ及７００～９００℃的硫蒸气中的硫化动力学、产物层的组成和结构进行了分析观察。结果表明，８８０℃加炉冷热处理的样品硫化时遵从抛物线规律，１０００℃加淬火样品则可表现出线性规律。合金的硫化速度比Ｆｅ２０Ｍｏ低１～２个数量级，但仍比纯Ｍｏ快得多。发现ＭｏＳ２层可在产物层中出现，其晶体的片层取向垂直于样品表面，有利于传质。合金硫化的活化能与纯Ｍｏ的接近，表明Ｆｅ４０Ｍｏ合金在实验条件下受其中Ｍｏ的硫化控制。

The sulfidation kinetics and scale structures of Fe40Mo alloy in 1kPa sulphur vapour at 700～900℃ were investigated with TGA,XRD,and SEM/WDS respectively.The alloy with a heat treatment history of heated at 880℃ plus cooled in furnace showed parabolic kinetics,while the specimens with heat treatment histroy of heated at 1000℃ plus quenched in cold water might behave the linear kinetics.Comparison to Fe20Mo alloy,Fe40Mo was sulfidized at a rate of 1～2 orders of magnitude slower,but still much faster than pure Mo.The sulfidation activation energy for Fe40Mo was close to that of pure Mo,predicting its controlling step was the sulfidation of Mo within alloy.MoS 2 layer could emerge in sulfide scales,and the orientation of the molecular laminate of MoS 2 lattice was perpendicular to the surface of specimens,i.e.parallelling to the direction of mass transfer across scale.This is beneficial to the particle diffusion and the scale growth.