高温高压水化学环境T22材质均匀腐蚀行为研究

General corrosion behavior of T22 material in high temperature and high pressure water chemical environment

本文在模拟高温气冷堆二回路的高温高压水化学环境下,研究了蒸汽发生器T22材质传热管在不同水化学环境中的均匀腐蚀行为。结果表明:提高溶液p H值、降低联氨质量浓度能够在一定程度上抑制T22材质的均匀腐蚀;随着反应温度升高,T22材质传热管均匀腐蚀速率加快;在高温高压水化学环境中,T22材质表面生成Fe3O4氧化膜,并随着反应时间的延长,Fe3O4晶粒尺寸逐渐长大,氧化膜致密性显著增加,导致T22材质均匀腐蚀速率显著降低,反应768 h后的T22材质均匀腐蚀速率降至0.016 g/(m^2·h)。

The general corrosion behavior of T22 material steam generator tube was studied in the simulating water chemical environment of secondary loop of high temperature gas cooled reactor.The results show that,the general corrosion of T22 material was inhibited to a certain extent by increasing the solution pH value and reducing the concentration of hydrazine.With the increase of reaction temperature,the general corrosion rate of T22 heat pipe was accelerated.In the high-temperature and high-pressure water chemical environment,Fe3 O4 oxide film was formed on the surface of T22,and Fe3 O4 grain size and compactness of oxide film increased significantly with the extension of reaction time,leading to a significant decrease in T22 general corrosion rate,which decreased to 0.0160 g/(m^2·h)after 768 hours’reaction.