包壳材料316Ti在液态铅铋中的腐蚀氧化层分析

Analysis on Corrosion Oxidation of 316Ti Cladding Material in Liquid Lead-bismuth Environment

本文利用自主研制的液态铅铋腐蚀试验装置,开展了中国铅基研究实验堆候选包壳材料316Ti在500℃氧饱和液态铅铋中3 000h的腐蚀试验。利用SEM及能谱仪对腐蚀后的样品进行了分析,结果显示316Ti样品腐蚀后形成了双层氧化膜,外层为疏松的Fe3O4氧化物,内层为致密的Fe-Cr尖晶石。随腐蚀时间的增加,外层氧化膜厚度变化不明显,但内层氧化膜逐渐增加,同时内层氧化膜沿晶界向基体生长,呈现出晶间腐蚀的特征。

316Ti has been selected as the candidate cladding material for China LEAd- based Research Reactor （CLEAR- I ）. In order to investigate the corrosion behaviors of 316Ti in lead-bismuth eutectic （LBE）, corrosion test was carried out in LBE saturated by oxygen at 500 ;C under saturated oxygen for 3 000 h. The results show that doublelayer oxide films are formed on 316Ti specimens. The outer layer is Fe304, while Fe-Cr spinel is found in the inner layer. The thickness of the outer layer keeps constant with increasing exposure time, while that of the inner layer increases with time. Furthermore, the inner layer grows into the 316Ti matrix along the grain boundaries, which indicates that intergranular corrosion occurs in our test.