含Ti、Mn或Nb的Fe-25Cr合金在800℃的H_2-H_2S混合气氛中的硫化

SULFIDATION PROPERTIES OF Ti, Mn ORNbBEARING Fe_25Cr ALLOYS IN H_2H_2S MIXEDENVIRONMENTS AT 800 ℃

研究了含４％Ｔｉ、９％Ｍｎ和８％Ｎｂ的Ｆｅ２５Ｃｒ合金在８００℃、１０－３～１Ｐａ硫分压范围内Ｈ２Ｈ２Ｓ混合气氛中的高温硫化，硫化动力学均基本遵循抛物线规律。当硫化层开裂或者与基体分离时，硫化增重—时间曲线出现转折。对比Ｆｅ２５Ｃｒ合金，３种元素的加入均不同程度地降低了硫化速度，但未根本改变硫化层结构。讨论了Ｆｅ２５Ｃｒ基三元合金的硫化过程及３种合金元素的作用。

The investigation on the hightemperature sulfidation properties of Fe_25Cr alloys containing 4%Ti, 9%Mn or 8%Nb in H_2H_2S mixed environments of 10^-3～1 Pa sulfur partial pressures at 800 ℃ was carried out. The sulfidation kinetics follows the parabolic law essentially. Turning aside from the parabolic law takes place when the sulfide scales crackes or seperates from the substrate at high temperature. Compared with the Fe25Cr alloy, the addition of these three elements reduce the sulfidation rate to varying degrees, but can not improve the sulfide scale structure. The sulfidation processes of Fe_25Cr alloys and the effect of alloying elements have been discussed.