摘要
通过循环氧化实验研究了不同时间和温度对合成尾气气氛中444铁素体不锈钢氧化效率和氧化铁皮形貌的影响。结果表明,444铁素体不锈钢在合成尾气环境中950℃下氧化总质量的变化幅度比较小,950℃下氧化100 h后单位面积上的增重与1050℃下的增重相比降低85.7%左右。氧化温度在950℃及1050℃时金属表面氧化铁皮大致可以分为两层。表层氧化产物主要由Fe-Cr尖晶石和Mn-Cr尖晶石组成,内层以Cr_(2)O_(3)为主。氧化铁皮与基体金属界面处存在硅元素氧化物富集层,以及靠近氧化铁皮的基体中出现富硅和钛的内氧化物。当在1050℃下氧化反应进行70 h后,试样表面出现瘤状氧化物,其外层主要为铁氧化物,内层主要为铁铬氧化物。1050℃下不锈钢氧化过程中氧化铁皮和基体界面上可见三种突出物,突出物与硅富集层长大相关。
The effect of different times and temperatures on the oxidation efficiency and iron oxide scale morphology of 444 ferritic stainless steel in the atmosphere of synthesis exhaust gas were studied by cyclic oxidation test.The results show that the change of total oxidation weight of stainless steel sample is relatively small at 950℃in the atmosphere of synthesis exhaust gas.The weight gain per unit area of the sample oxidized at 950℃for 100 h is about 85.7%less than that oxidized at 1050℃for 100 h.The increase in temperature increases the oxidation rate of stainless steel and accelerates the breakaway oxidation process.When the oxidation temperatures are 950℃and 1050℃,the iron oxide scale on the metal surface can be roughly divided into two layers.The surface oxidation products are mainly composed of Fe-Cr spinel and Mn-Cr spinel.The inner layer is primarily Cr_(2)O_(3).There is a silicon oxide enrichment layer at the interface between the iron oxide scale and the substrate,and there are silicon and titanium internal oxides in the substrate near the iron oxide scale.When the oxidation reaction temperature is 1050℃and the oxidation time is 70 h,oxide nodules are produced on the oxide scale.The oxide nodules’outer layer is mainly iron oxide,and the inner layer is primarily iron chromium oxide.When stainless steel was oxidized at 1050℃,three kinds of protrusions were observed at the interface between the iron oxide scale and substrate.The protrusions were trapped in the silicon enrichment layer and iron oxide scale and almost disappeared after 100 h of oxidation.The growth of the silicon-enriched layer is related to protrusion formation.
作者
高圣伦
孙彬
程磊
刘振宇
GAO Shenglun;SUN Bin;CHENG Lei;LIU Zhenyu(Institute of Mechanical Engineering,Shenyang University,Shenyang 110044,China;State Key Laboratory of Rolling Technology and Automation,Northeastern University,Shenyang 110819,China)
出处
《材料导报》
CSCD
北大核心
2023年第24期223-229,共7页
Materials Reports
基金
国家自然科学基金(51301111)
辽宁省自然基金(2019-KF-05-04)
沈阳市中青年科技创新人才支持计划(RC200387)。
关键词
铁素体不锈钢
高温氧化
合成尾气
失稳氧化
ferritic stainless steel
high temperature oxidation
synthetic exhaust gas
breakaway oxidation
