摘要
采用动电位扫描,恒电位浸蚀以及金相检测等方法,研究了不锈钢双相组织在酸性介质中发生选择性腐蚀的机理。研究发现,选择性腐蚀与体系所处的氧化-还原电位有关。在活化区的低电位段发生铁素体相的选择性腐蚀,较高电位段则发生奥氏体相的选择性腐蚀,两者之间存在一个两相腐蚀区;在过钝化区和近过钝化区,腐蚀优先发生在铁素体相上,然后向奥氏体相扩展。
The preferential dissolution mechanisms of duplex weldments of stainless steels have been investigated by means of potentiodynamic scanning and potentiostatic etching in acid solutions containing chloride. It was observed that the preferential dissolution of duplex weldments depended on the electrochemical potential. Both in the transpassive region and the lower part of the active range existed the preferential dissolution of ferritic phase. The preferential dissolution of austenitic phase took place in the higher potential part of the active range. There was a duplex phase corrosion range between the lower and higher potentiol of active range. In the transpassive and near transpassive regions dissolution took place in ferritic phase preferentially, then expanded to austenitic phase. The influence of chloride concentration and temperature on preferential dissolution of duplex weldments is also discussed.
出处
《腐蚀科学与防护技术》
CAS
CSCD
1993年第4期238-243,共6页
Corrosion Science and Protection Technology
关键词
不锈钢
焊缝
腐蚀
研究
stainless steels
duplex weldments
preferential dissolution
