供水管道中球墨铸铁与H62黄铜的电偶腐蚀行为研究  

Galvanic Corrosion Behavior of Ductile Iron/H62 Brass in Water Distribution System

作　　者：汤甜 朱志平[1] 唐韵子 刘健 毛春奎 TANG Tian;ZHU Zhiping;TANG Yunzi;LIU Jian;MAO Chunkui(Department of Chemistry and Chemical Engineering,Changsha University of Science and Technology,Changsha 410114,China;Changsha Water Supply Company,Changsha 410035,China)

机构地区：[1]长沙理工大学化学化工学院,湖南长沙410114 [2]长沙供水有限公司,湖南长沙410035

出　　处：《材料保护》2024年第7期93-101,共9页Materials Protection

基　　金：湖南省教育厅科学研究重点项目(23A0269)。

摘　　要：为探讨自来水管网中球墨铸铁与H62黄铜供水管连接存在的电偶腐蚀问题,在模拟酸性工业大气腐蚀条件下,采用电化学噪声(EN)测试、能谱仪、扫描电镜考察了不同温度(0、25、40℃)、不同阴阳极面积比(S_(c)∶S_(a)=1∶1、2∶1、4∶1)时球墨铸铁/H62黄铜电极的电偶腐蚀电流、腐蚀形貌及腐蚀产物成分情况。结果表明:球墨铸铁/H62黄铜电极偶接时,球墨铸铁作为阳极,电偶腐蚀电流密度为其自腐蚀时的3.46倍;随着温度升高,电偶对的阳极腐蚀加剧;随着S_(c)∶S_(a)的增大,电偶腐蚀电流密度增大;电化学噪声I_(g)-t和E_(g)-t谱揭示了电偶对的阳极保护膜被破坏、发生孔蚀时的电荷变化情况。电偶效应促进了阳极球墨铸铁点蚀的发生。In order to investigate the galvanic corrosion of the connection between ductile cast iron and H62 brass water pipe in tap water supply network,electrochemical noise(EN),EDS,SEM and other methods were used to investigate the galvanic corrosion current,corrosion mor-phology and corrosion product composition of ductile cast iron/H62 brass electrode at different temperatures(0℃,25℃,40℃)and the specific surface area ratios of anode and cathode(S_(c)∶S_(a)=1∶1、2∶1、4∶1)under the condition of simulated acidic industrial atmospheric corrosion.Results showed that when the nodular cast iron/H62 brass electrode was coupled,the nodular cast iron served as the anode,and the galvanic corrosion current density was 3.46 times that of its self-corrosion process.The anode corrosion of couple pair was intensified with the increase of temperature.With the increase of S_(c)∶S_(a),the galvanic corrosion current density increased.Furthermore,the I_(g)-t and E_(g)-t spectra of electrochemical noise revealed that the change in charge when the anode protection film of the electric couple pair was damaged and pitting occurred.Hence,the galvanic effect promoted the occurrence of pitting corrosion in anode ductile iron.

关 键 词：球墨铸铁 H62黄铜 电偶腐蚀 腐蚀电流 电化学噪声 

分 类 号：TG172[金属学及工艺—金属表面处理]