NF709奥氏体耐热钢700℃的蒸汽氧化行为  

Steam Oxidation Behavior of Austenitic Heat Resistant Steel NF709 at 700 ℃

作　　者：王斌[1,2] 刘正东[1] 程世长[1] 刘春明[2] 包汉生[1] 王敬忠[1] 

机构地区：[1]钢铁研究总院特殊钢研究所,北京100081 [2]东北大学材料与冶金学院,沈阳110004

出　　处：《腐蚀与防护》2013年第4期279-282,共4页Corrosion & Protection

基　　金：国家科技支撑计划(2007BAE51B02);钢研-宝钢研究课题(2007-170)

摘　　要：采用氧化增重法、扫描电镜(SEM)和X射线衍射分析(XRD)研究了奥氏体耐热钢NF709在700℃高温蒸汽下的氧化动力学、氧化层形貌及成分分布。结果表明,该钢700℃蒸汽氧化动力学曲线符合Δm=ktz规律;随着氧化时间的增长,氧化层明显增厚,分层现象明显,可分为内、外两层。外层较厚,为疏松多孔结构的富铁氧化物,内层较薄,为致密的尖晶石结构的富铬氧化物。内层氧化物有效地阻止了元素的扩散,降低了氧化速率。The oxidation kinetics, the morphology and distribution of chemical composition of oxidaion layers for NF709 austenite heat-resisting steel in water vapor at 700℃ were studied by the oxidation weight gain method, SEM with EDS and XRD. The results indicate that the oxidation kinetics of this steel under water-vapor condition follows parabolic equation △m=kt^zat 700 ℃. The thickness of oxidation layer increased with test time. The oxidation scale consists of two layers, the outer layer rich in Fe oxide with a loose and porous structure is more thicker than the inner layer rich in Cr oxide with dense spinel structure. The element diffusion was retarded by the inner layer and so the oxidation rate decreased.

关 键 词：NF709奥氏体耐热钢 蒸汽氧化 氧化动力学 氧化层 

分 类 号：TG172.5[金属学及工艺—金属表面处理]