奥氏体不锈钢管内壁氧化物脱落原因分析及检测方法探讨

Analysis on the Falling-off Problem of Oxides on the Inside Wall of Austenitic Stainless Steel Pipe and Its Examining Method Study

指出电站锅炉奥氏体不锈铜管内壁氧化物脱落的原因是奥氏体钢的金属基体晶格为面心主方晶格,与氧化膜的晶格差异较大,因而二者的热膨胀系数相差也较大,氧化膜与基体结合不紧密,分析了氧化物的结构、形成机理及其危害性,总结分析了对脱落的氧化物进行检测的方法(射线检测法、磁强法),并指出只有二种方法结合使用才会得到既快又好的效果。

It was indicated in the paper that, the cause of falling-off of oxides on the inside wall of austenic stainless steel pipe in the fossil-fired power plant was, the metallic base crystal lattice of austenic steel was face-centred cubic lattice, greatly different from the lattice of oxide film. As a result of the great difference of thermal expansion coefficients of both, oxide film couldn＇ t combine with basic matter tightly. The paper analyzed the configuration, forwation mechanism of oxides and its harmfulness, summed up and analyzed the examining method of falling-off oxides,i.e., radiation examining method and magnetometry, and indicated that only the combining use of both methods could achieve the better effect.