9Ni钢铸坯在900~1250℃空气中的高温氧化行为  

Oxidation Kinetics of 9Ni Steel Billet at High Temperature

作　　者：郭涛 黄峰[1] 胡骞[1] 刘静[1] GUO Tao;HUANG Feng;HU Qian;LIU Jing(State Key Laboratory of Refractories and Metallurgy,Hubei Engineering Technology Research Center of Marine Materials and Service Safety,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学、省部共建耐火材料与冶金国家重点实验室、湖北省海洋工程材料及服役安全工程技术研究中心,武汉430081

出　　处：《中国腐蚀与防护学报》2023年第4期882-889,共8页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(U21A20113)。

摘　　要：采用热分析-质谱仪联用系统,结合场发射扫描电子显微镜(FE-SEM)、场发射电子探针显微镜(FEEPMA)、X射线衍射(XRD)等表面测试技术及FactSage10.0热力学软件研究了9Ni钢铸坯在900~1250℃的氧化热、动力学行为。结果表明:9Ni钢在900~1250℃区间的恒温氧化,基本都遵循抛物线规律,氧化速率受金属离子在氧化膜中的扩散控制;Ni在内氧化层中以FeNi3和NiFe2O4形式存在,在内外氧化层交界处则以Ni单质富集,且与Fe的氧化物相互缠结;9Ni钢铸坯发生晶界高温腐蚀主要是由于Si氧化后生成的SiO_(2)会与铁氧化产物FeO反应形成Fe_(2)SiO_(4)(铁硅橄榄石),当温度高于其共晶温度(约1170℃),铁硅橄榄石呈液态是由于向基体中的奥氏体晶界进行不规则渗透所致。The oxidation behavior of 9Ni steel slab at 900~1250℃were investigated by employing a combined thermal analysis and mass spectrometer system,field emission scanning electron microscopy(FE-SEM),field emission electron probe microscopy(FE-EPMA),X-ray diffractometer(XRD)and soft wear FactSage10.0.The results show that the constant temperature oxidation of 9Ni steel at 900-1250℃mainly follows the parabolic law,and the oxidation rate is controlled by the diffusion of metallic ions in the oxide layer,Ni exists in the oxide layer in the form of FeNi3 and NiFe2O4 in the inner layer,and elemental Ni enriched at the boundary of the inner/outer layers of the formed oxide scale,and intertangled with Fe-oxides,The high temperature corrosion at grain boundaries of 9Ni steel billet should be attributed to Fe_(2)SiO_(4)(ferrosilicon olivine)which come from the combining of SiO_(2)generated by Si oxidation and FeO of the product of iron oxidation,When the temperature is higher than the eutectic temperature(about 1170℃),ferrosilicon olivine will be irregularly permeated into austenite grain boundaries in the matrix as liquid.

关 键 词：9Ni钢铸坯 氧化铁皮结构 网络状组织 晶界高温腐蚀 

分 类 号：TG174[金属学及工艺—金属表面处理]