奥氏体耐热不锈钢309S高温抗氧化性能研究

High Temperature Oxidation Resistance of 309S Austenitic Stainless Steel

采用不连续称重法测得了奥氏体耐热不锈钢309S在不同温度下的高温氧化动力学曲线,结果表明309S钢高温氧化动力学曲线遵循抛物线规律。利用扫描电镜、X射线衍射和XPS的方法对氧化膜表面的形貌及化学元素沿氧化膜纵深方向的分布情况进行了研究,发现各温度下的氧化膜均均匀覆盖于基体表面;500℃下氧化膜氧化产物表层主要为Cr2O3和Fe2O3,内层主要为Cr2O3和NiO;1 000℃下氧化膜表层主要成分为Cr2O3、NiO、Fe3O4或Fe2O3,氧化膜内层基本不含NiO,主要为Cr2O3、Fe3O4或Fe2O3。

Kinetic curves of 309S at various temperatures,which were found to be parabolic,were obtained by weight gain method.Morphology of oxide scale and phase composition along depth direction were studied by SEM,XRD and XPS.The result indicated that substrates were continuously covered by oxide at different temperature.At 500 ℃,outer layer of the scale was mainly composed of Cr2O3 and Fe2O3,however,Cr2O3 and NiO were predominant phase in inner layer of the scale;at 1 000 ℃,the outer layer of the scale was mainly composed of Cr2O3 ,NiO, Fe3O4 or Fe2O3 ; while in inner layer of the scale, NiO was negligible and Cr2O3, Fe3O4 or Fe2O3 were predominant phase.