针对核电厂凝汽器二次滤网及旋转滤网用铝合金牺牲阳极存在溶解不足及阴极保护效果不佳的情况,对相关海水水质、牺牲阳极化学成分和电化学性能进行分析,研究了铝合金牺牲阳极失效的原因。结果表明:阳极中主要合金元素In含量偏低、杂质元素Si含量偏高是其性能变差的主要原因。建议核电厂在牺牲阳极采购过程中严格把控原材料化学纯度,对进厂牺牲阳极进行表面质量、化学成分复验和电化学性能测试,在上述性能均满足相关标准和技术要求后方可使用。

In view of insufficient dissolution and poor cathodic protection effect of aluminum alloy sacrificial anode for secondary filter screen and rotary filter screen of condenser in a nuclear power plant, the relevant seawater quality, chemical composition and electrochemical performance of sacrificial anode were analyzed to studied the failure causes of the aluminum alloy sacrificial anode. The results showed that the low content of main alloy element In and high content of impurity element Si were the main reasons for the worsening performance of the anode. It was advised to strictly control the material quality during the procurement of sacrificial anode. The surface quality, chemical composition and electrochemical performance of the sacrificial anode entering the factory should be tested, and the above performance should meet the relevant standards and technical requirements before application.