工业纯Ti在模拟高放废物地质处置环境中的缝隙腐蚀行为  

CREVICE CORROSION OF GRADE-2 Ti IN SIMULATED GROUNDWATER FOR GEOLOGICAL DISPOSAL OF HIGH-LEVEL RADIOACTIVE NUCLEAR WASTE

作　　者：魏欣[1,2] 董俊华[2] 柯伟[2] 

机构地区：[1]大连理工大学材料科学与工程学院,大连116024 [2]中国科学院金属研究所金属腐蚀与防护国家重点实验室,沈阳110016

出　　处：《金属学报》2013年第6期675-681,共7页Acta Metallurgica Sinica

基　　金：国家自然科学基金资助项目51071160~~

摘　　要：采用动电位极化曲线、电化学阻抗谱、电偶电流监测及恒电位极化等电化学方法研究了温度和C1-浓度对Grade-2 Ti在模拟高放废物处置环境中缝隙腐蚀行为的影响.结果表明,浸泡初期,带缝隙Ti电极在25—95℃时均呈现钝化特征.随浸泡时间延长,缝隙内介质环境侵蚀性增强,诱发Ti缝隙腐蚀.随着温度的升高和Cl^-浓度的增加,电偶电流增大,Ti的耐缝隙腐蚀性能下降.Ti缝隙腐蚀各阶段转变的临界温度随着Cl^-浓度和外加电位的增加而降低.由于发生阳极活性溶解,缝隙口处金属被严重破坏.The influences of temperature and C1- concentration on the crevice corrosion of grade-2 Ti in the simulated geological disposal environment of high-level radioactive nuclear waste were investigated by potentiodynamic polarization curves, electrochemical impedance spectroscopy, galvanic current monitoring and potentiostatic polarization. The results showed that all the creviced specimens exhibited the passive characteristics in the initial immersion period at 25 95 ~C. With extending the immersion time, the crevice corrosion of Ti initiated as a result of the gradual aggressive environment （higher C1- concentration and more acidification） in the crevice. As increasing the temperature and C1- concentration, the galvanic current increased and the crevice corrosion resistance was decreased. In addition, the critical temperature of crevice corrosion decreased with increasing C1- concentration and the applied potential. The damage caused by anodic active dissolution in the crevice mainly located near the crevice mouth.

关 键 词：高放废物 TI 缝隙腐蚀 温度 

分 类 号：TG174.3[金属学及工艺—金属表面处理]