摘要
采用模拟闭塞电池法和交流阻抗法研究了奥氏体304不锈钢形变诱发马氏体相变对点蚀发展过程中化学和电化学行为的影响。结果表明,随着马氏体含量的增加,闭塞区溶液pH值下降得更快,Cl-迁入闭塞区的量更多。马氏体相的存在增强了材料的电化学活性,既减小了点蚀发展过程中钝化膜孔隙内的欧姆电阻,又减小了孔隙内的反应极化电阻,从而促进了点蚀发展。
By using simulated occluded corrosion cell (OCC) method and electrochemical impedance spectroscopy (EIS) techniques, the chemical and electrochemical changes during the pitting propagation of austenitic 304 stainless steel which had deformation-induced martensite transformation were studied. The results showed that more martensite phase in the specimen resulted in quicker falling of the pH of OCC solution and more Cl^- migrated into OCC. The results also indicated that martensite phase increased the electrochemical activity of the material, decreased the ohmic resistance and faradic impedance in pits in the passive film. Those mean that martensite phase increases anodic dissolution and pitting propagation.
出处
《腐蚀与防护》
CAS
2004年第12期507-509,512,共4页
Corrosion & Protection
基金
国家重点基础研究发展规划项目(G19990650)
关键词
304不锈钢
马氏体
点蚀
模拟闭塞电池
交流阻抗
304 stainless steel
Martensite
Pitting
Occluded corrosion cell
Electrochemical impedance spectroscopy