Fe－25Cr－9Mn三元合金高温硫化特性

HIGH-TEMPERATURE SULFIDATION BEHAVIOUR OF AN Fe-25Cr-9Mn TERNARY ALLOY

研究了Ｆｅ－２５Ｃｒ－９Ｍｎ合金在８００℃、１０－３─１Ｐａ硫分压的Ｈ２－Ｈ２Ｓ混合气体中的硫化行为，并与Ｆｅ－２５Ｃｒ合金进行了对比。结果表明：Ｍｎ的加入提高了Ｆｅ－２５Ｃｒ合金的抗硫化性能，但作用并不显著。在Ｆｅ－２５Ｃｒ－９Ｍｎ合金的多层结构硫化层中形成了较厚且独立的α－（Ｍｎ．Ｆｅ）Ｓ层，但它并没有效地阻挡Ｆｅ２＋和Ｃｒ３＋向外的扩散。文中讨论了这种现象的原因以及硫化层分层对铁铬合金硫化行为的影响。

The sulfidation behaviour of an Fe-25Cr-9Mn alloy in H2-H2S mixed gases. with the sulfur partial pressures in the range of 10-3 to 1Pa, at 800℃ has been investigated in comparision with Fe-25Cr. The results showed that the addition of Mn improved the sulfidation resistance of Fe-25Cr. but the effect was not considerable. A rather thick individual χ-(Mn.Fe)S layer formed in the multilayered sulfide scale of Fe-25Cr-9Mn, but it did not act as an effective barrier to the outward diffusion of Fe2+ and Cr3+ ions. The reasons for this phenomenon and the influence of the sulfide scale demixing on the sulfidation process of Fe-Cr alloys have been discussed.