中性盐雾腐蚀环境中B340LA钢板的腐蚀周期性研究

Corrosion Periodicity Research of B340LA Steel Plate in Neutral Salt Spray Corrosion Environment

为了探究B304LA钢在大气沿海环境下的腐蚀情况,在中性盐雾腐蚀环境中对B340LA钢板进行0～50d的连续喷雾腐蚀试验,采用扫描电子显微镜对未除去表面腐蚀产物的截面进行观察分析,观察表面锈层分层情况;通过X射线衍射仪(XRD)和电子探针(EPMA)分析了腐蚀产物的结构及锈层内合金元素的分布;采用电化学工作站对锈层进行了交流阻抗谱曲线测定。结果表明:B340LA钢板在中性盐雾条件下随着腐蚀天数的增加腐蚀速率呈先增大后减小、然后继续增大的趋势,交流阻抗容抗弧半径不断减小,腐蚀产物主要由β-FeOOH、α-FeOOH、γ-FeOOH、Fe3O4等组成。

In order to study the corrosion performance of B304LA steel in coastal atmosphere environments,the B340LA steel plate was continuously spray-etched in the neutral salt spray environment for 0-50 days. The cross-section morphology of the surface corrosion products and the delamination phenomenon of the surface rust layers were observed by scanning electron microscopy( SEM). In addition,X-ray diffractometer( XRD) and electron probes( EPMA) were employed to characterize the structure and element distribution in the rust product layers. The electrochemical workstation was used to determine the EIS curves of the rust layers. Results showed that the corrosion rate of B340LA steel plate increased first and then decreased,and then continued to increase with increasing number of corrosion days under neutral salt spray conditions.The arc radius of AC impedance capacitance decreased continuously. Moreover,the corrosion products mainly consisted of β-FeOOH,α-Fe OOH,γ-Fe OOH,Fe3O4 and other components.