摘要
采用失重法和电化学方法,通过腐蚀形貌观测、腐蚀产物元素分析和物相分析研究了再生水中常见的大肠埃希氏菌(Escherichiacoli,Eoil)对QT500-7球墨铸铁腐蚀行为的影响。失重腐蚀试验表明:含菌体系中铸铁的失重腐蚀速率高于无菌体系,并且随着腐蚀时间的延长,含菌体系与无菌体系腐蚀速率的比值持续增大,说明Eoil对铸铁的腐蚀具有明显的促进作用。电化学测试结果表明:试验周期内,含菌体系的自然腐蚀电位比无菌体系低,铸铁的腐蚀倾向更大。浸泡8d后,含菌体系的腐蚀电流约是无菌体系的6倍,电荷转移电阻R_(ct)约是无菌体系的1/10。电化学测试结果和失重腐蚀试验结果相吻合,在培养基中铸铁在Eoil影响下的腐蚀形态为点蚀。含菌体系的铸铁腐蚀产物中Fe元素和O元素的含量明显高于无菌体系,铸铁在含菌和无菌环境下的腐蚀产物主要成分均为Fe(OH)_(2)和α⁃FeOOH,这说明Eoil加速了腐蚀的进程,但并未改变腐蚀的途径。
The influence of Escherichia coli(Eoil)on the corrosion behavior of QT500-7 ductile iron in reclaimed water is studied by using weight loss method and electrochemical method,with observing corrosion morphology,analyzing the element and phase of the corrosion products.Weight loss corrosion experiments show that the corrosion rate of cast iron in Eoil system is higher than that in sterile system,and the ratio of the corrosion rate between Eoil system and sterile system increases with the time.Eoil has an obvious promoting effect on the corrosion of cast iron.The electrochemical test results show that the natural corrosion potential of the Eoil system is lower than that of the sterile system,whose cast iron is greater.After soaked for 8 days,the corrosion current of the bacteria containing system is about 6 times of that of the sterile system,whose charge transfer resistance(R_(ct))is about 1/10 of that of the sterile system.The results of electrochemical test are in good agreement with those of weight loss corrosion test.The corrosion morphology of cast iron under the influence of Eoil is pitting corrosion in the culture medium.The contents of Fe and O elements in the corrosion products of cast iron with bacteria are obviously higher than those in the sterile system.While the main components of the corrosion products of cast iron with bacteria and in the sterile environment are both Fe(OH)_(2 )andα-FeOOH,indicating that Eoil accelerates the corrosion process but does not change the corrosion path.
作者
杨光明
孟俊臣
林莉
范金龙
龚敏
曾宪光
YANG Guangming;MENG Junchen;LIN Li;FAN Jinlong;GONG Min;ZENG Xianguang(School of Materials Science and Engineering,Sichuan University of Science&Engineering,Zigong 643000,China;Material Corrosion and Protection Key Laboratory of Sichuan Province,Zigong 643000,China)
出处
《四川轻化工大学学报（自然科学版）》
CAS
2022年第1期42-50,共9页
Journal of Sichuan University of Science & Engineering(Natural Science Edition)
基金
四川省科技厅重点研发计划项目(22SYSX0129)
材料腐蚀与防护四川省重点实验室开放基金项目(2020CL18)
四川轻化工大学研究生创新基金资助项目(y2020074)。
作者简介
杨光明(1996-),男,硕士生,研究方向为腐蚀与防护、电化学,(E-mail)ygm1249947206@163.com;通信作者:龚敏(1963-),女,教授,研究方向为材料腐蚀与防护,(E-mail)gongmin@suse.edu.cn。
