D0I:10.13374/i.issm1001-053x.1989.06.035 第11卷第6期 北京科技大学学推 Vol.11 No.6 1989年11月 Journal of University of Science and Technology Beijing No7.1989 High Temperature Corrosion of Fe-25Cr and Fe-17Cr-1.5Si-0,5Al Alloys in Oxidizing and Sulfidizing Enviornments' Wang C@irong(王才荣)，。Gong Maoxiu(公茂秀)， Zhang Wengi(张文奇)，Zhu Rizhang（来日彰)。 ABSTRACT:The simultaneous oxidation and sulfidation of Fe 25Cr and Fe- 17Cr-1.5Si-0.5Al alloys was studied at 1023K and 1223K in Ha-H,O-H,S gas mixtures.The kinetic boundary which indicates the transition from oxide to sulfide has heen found in these two alloys.The critical oxygen partial pressures of Fe17Cr1.5Si0.5Al alloys were systematically lower than those of Fe-25Cr alloy.The reaction kinetics were measured by the stainless steel spring balance, and the reaction products were characterized by X-ray diffraction and scanning electron microscopy.The reaction rate usually decreased with the increase of the oxygen partial pressure at the constant sulfur partial pressure.The exista- nce of silicon plays an important role to suppress the sulfidation of Fel7Cr alloy. KEY WORDS:high temperature corrosion,Fe-Cr alloy,oxidizing,sulfidizing In technical processes,metallic materials are often exposed to the gases con- taining more then one oxidant.The combustion gases of fossil fuels or gases formed by coal gasification processes contain compounds of element O,S,C. Generally,the sulfidation is the main reason for the degradation of metallic materials at high temperatures in industrial environments.The understanding of the simultaneous sulfidation and oxidation,or the suppression of sulfide forma- tion,in particular,is of technical importance. Recent investigationst 1-51 have shown that all the iron-nickel and cobalt-based technical and model alloys exhibit in such atmospheres the existance of simulta- necus sulfidation and oxidation.In the simultaneous sulfidation and oxidati.n processes there exists a transition from oxide to sulfide.This transition is also Manuscript Received Jan.24,1989 ..Dept.of Surface Science and Corrosion Engineering ···Shandong Institute of Metallurgical Design-Rescarch 604第 卷第 期 ， 年 月 北 京 料 技 大 学 学 报 ，。 一，，时。 。 ， ，。 ， 一 一 一 。 一 ’ 甲。 。 夕 ‘ 王 才荣 ， ’ ， 对 。 “ 公 茂秀 ，… 平，， 张文 奇 二 ， 君 朱 日彩 二 一 。 一 。 了 一 一 · 众 了 。 “ “ 五 了 。 了 一 。 了 ， 让 一 一 。 五 ， 一 ， 盆 ， ‘ ， 田 五 ， ， ， 立 一 五 ， ， ， 一 ‘ 一 一 。 二 ‘ 峨， ， … 一 才 DOI ：10．13374／j ．issn1001－053x．1989．06．035