Effect of polyacrylic acid on the corrosion behavior of Alloy 690 in pressurized water reactor secondary water
作者
单位
1CAS Key Laboratory of Nuclear Materials and Safety Assessment、Institute of Metal Research、Chinese Academy of Sciences、Shenyang、110016、China 2School of Materials Science and Engineering、University of Science and Technology of China、Shenyang、110016、China 3Institute of Corrosion Science and Technology、Guangzhou、510530、China
关键词
收录来源
International Corrosion Congress · 第22届国际腐蚀大会
摘要
The effect of polyacrylic acid (PAA) on the corrosion behavior of Alloy 690 in simulated pressurized water reactor secondary water was investigated. The duplex oxide film structure, consisting of a Ni -rich outer layer and a Cr -rich inner layer, was maintained regardless of PAA presence. PAA inhibited the growth of outer Ni -rich particles while promoting Cr enrichment in the inner layer and inducing its amorphization, both enhancing oxidation resistance. However, excess PAA (≥ 500 ppb) suppressed protective oxide formation during initial oxidation, leading to oxygen penetration into the matrix. A PAA concentration of around 250 ppb is considered optimal for steam generators, as it provides the benefits of PAA without adverse effects on the alloy.