TP347H和Sanicro25在700℃高温水蒸气中的氧化行为研究

Study on Oxidation Behavior of TP347H and Sanicro25 in Water Vapor at 700℃

研究了奥氏体不锈钢TP347H和Sanicro25在700℃、5 MPa高温水蒸气环境中的氧化行为,氧化1000 h后采用增重法和厚度法获得2种合金的氧化动力学规律,利用扫描电镜和能谱仪分析了氧化物的形貌和元素分布,利用X射线衍射仪对样品表面氧化物进行物相分析。结果表明:2种合金的氧化动力学行为基本符合抛物线规律,氧化物的形成和剥落均分为6个阶段,Sanicro25样品的抗蒸汽氧化性能优于TP347H样品;TP347H氧化膜外层主要是Fe_(2)O_(3)和Fe_(3)O_(4),内层主要是(Fe,Cr)_(3)O_(4);Sanicro25氧化膜外层主要是Fe_(2)O_(3)和Fe_(3)O_(4),内层主要是(Fe,Cr)_(3)O_(4)和Cr_(2)O_(3)。

The oxidation behavior of austenitic stainless steel TP347H and Sanicro25 in high temperature steam environment at 700℃/5 MPa was studied.After oxidation for 1000 h,the oxidation kinetics of two alloys were obtained by weight gain method and thickness method.The morphology and element distribution of the oxides were analyzed by scanning electron microscope and energy dispersive spectrometer,and the phase analysis of the oxides on the surface of the samples was carried out by X-ray diffractometer.Results show that the oxidation kinetic behavior of two alloys basically conforms to the parabolic law,and the formation and exfoliation of oxides are divided into six stages.The steam oxidation resistance of Sanicro25 is better than that of TP347H.The outer layer of TP347H oxide film consists of Fe_(2)O_(3)and Fe_(3)O_(4)mainly,and the inner layer is(Fe,Cr)_(3)O_(4)mainly.The outer layer of Sanicro25 oxide film consists of Fe_(2)O_(3)and Fe_(3)O_(4)mainly,and the inner layer is(Fe,Cr)_(3)O_(4)and Cr_(2)O_(3)mainly.