以0.1 mol·L^-1NaCl+0.01 mol·L^-1NaHSO3溶液为腐蚀介质,采用干/湿周浸加速腐蚀实验、腐蚀失重、X射线衍射、扫描电镜和能谱分析等方法,研究了湿热工业海洋大气中低碳钢的腐蚀行为.结果表明:实验钢的腐蚀过程均遵循幂函数d=At~n分布规律,钢种不同,常系数A、n的值不同;腐蚀产物主要由非晶物质和少量Fe3O4、α-FeOOH、β-FeOOH、γ-FeOOH晶体组成.所得锈层可分为主体锈层和界面疏松带两部分,由内至外锈层中Fe、O含量梯度变化很小.Cl^-、SO2与水分的长期协同作用会导致内锈层结构变差,而添加稳定性或耐蚀性较高的元素可以改善锈层质量,进而增强钢材的耐腐蚀性能.
The corrosion behavior of low-carbon steel was investigated in a simulated hot and humid industrial-marine atmosphere by X-ray powder diffraction (XRD) , scanning electron microscopy with X-ray microanalysis (SEM-EDS) , mass loss, and a wet/dry alternate immersion corrosion test using a 0. 1 mol· L^-1 NaCl + 0. 01 mol·L^-1 NaHSO3 solution. The results indicate that the corrosion processes of the experimental steels agree well with the d = Atn power function, with different steels having different values of A and n. The corrosion products are mainly in the amorphous phase and contain a small amount of Fe3O4 , α-FeOOH, β-FeOOH, and γ-FeOOH crystals. It can he found that the rust layers have two parts-the body of the rust layer and a loose interface band. The Fe and O content gradients in the rust layer, from inner to outer, change very little. It can be concluded that the long-term interaction of Cl^- , SO2 and HE O will lead to the deterioration of the inner structure. However, the addition of elements with high stability or corrosion resistance can improve the stability and density of the rust layer, and thereby enhance the corrosion resistance of the steels.