马氏体相变对304不锈钢点蚀发展过程的影响  

INFLUENCE OF MARTENSITE TRANSFORMATION ON PITTING PROPAGATION OF TYPE 304 STAINLESS STEEL

作　　者：胡钢[1] 许淳淳[1] 张新生[1] 

机构地区：[1]北京化工大学材料科学与工程学院,北京100029

出　　处：《腐蚀与防护》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)

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.

关 键 词：304不锈钢 马氏体 点蚀 模拟闭塞电池 交流阻抗 

分 类 号：TG174.3[金属学及工艺—金属表面处理]