核电站不锈钢覆面焊接接头的点蚀行为及设计改进  

Pitting Corrosion Behavior and Design Improvement for the Welds of Steel Liner of Nuclear Power Plants

作　　者：王宇欣 白林 张洪军 邰江 左景辉[2] 张跃 WANG Yuxin;BAI Lin;ZHANG Hongjun;TAI Jiang;ZUO Jinghui;ZHANG Yue(China Nuclear Power Engineering Co.,Ltd..Beijing 100840,China;Institute of Metal Research Chinese Academy of Sciences,Shenyang 110016,China;Nuclear and Radiation Safety Center,Beijing 100082,China)

机构地区：[1]中国核电工程有限公司,北京100840 [2]中国科学院金属研究所,沈阳110016 [3]生态环境部核与辐射安全中心,北京100082

出　　处：《腐蚀与防护》2021年第7期59-65,共7页Corrosion & Protection

摘　　要：采用电化学方法研究了Cl^(-)含量、温度、介质pH、SO42-含量、含氧量对S30403、S32101和S32205不锈钢焊接接头在硼酸溶液中点蚀行为的影响。结果表明:S32205焊接接头对温度的影响更为敏感,对Cl^(-)和SO42-不敏感,且存在临界温度区Tb0>60℃、40℃<Tr0<60℃,在区间内点蚀电位E_(b)和再钝化电位Er分别急剧降低;S32101和S30403焊接接头的E_(b)和E_(r)基本接近,对Cl^(-)更为敏感,对温度和SO_(4)^(2-)不敏感。介质中溶解氧浓度对S32205焊接接头的Eb和Er的影响较大,但对S32101和S30403焊接接头的影响不明显;焊接接头的点蚀电位随温度变化的规律与基材的基本相同。The pitting corrosion resistance behaviors of S30403,S32101 and S32205 stainless joints were studied under the condition of boric acid as electrochemical solution with different Cl^(-)content,temperatures,pH,SO42-and oxygen concentrations.The results show that the S32205 joints were more sensitive to temperature than to Cl^(-)and SO42-,and pitting corrosion potential(E_(b))and repassivation potential(E_(r))respectively decreased obviously in critical temperature ranges of Tb0>60℃,40℃<Tr0<60℃.The Eb and Er of S32101 and S30403 were almost the same,which were more sensitive to Cl^(-)than to the temperature and SO_(4)^(2-).The pitting corrosion potential and repassivation potential of S32205 joints were more sensitive to oxygew content than those of S30403 and S32101 joints.The change rule of temperature effect on pitting corrosion potential for joints were basically the same for base materials.

关 键 词：不锈钢覆面 焊接接头 点蚀电位 再钝化电位 

分 类 号：TG174[金属学及工艺—金属表面处理]