摘要
分别设计了金属-金属、金属-四氟乙烯、金属-橡胶、金属-塑料薄膜4种接触类型,探究不同类型接触面对不锈钢缝隙腐蚀的影响。对316L奥氏体不锈钢的缝隙构型进行FeCl3浸泡实验和电化学实验,研究了其对缝隙腐蚀行为的影响,通过激光共聚焦显微镜对缝隙腐蚀后样品的宏观形貌进行了研究。结果表明,金属-金属接触面条件下腐蚀形貌宽度最大,深度最浅,蚀坑横向发展,蚀坑达到一定深度后,腐蚀溶液横向扩散更容易。金属-橡胶接触面下腐蚀形貌宽度最小,深度最大,蚀坑纵向发展,这与橡胶所受应力有关,始终紧贴样品表面,腐蚀溶液不易发生横向扩散。电化学测试表明,不同类型接触面缝隙试样的破钝化电位相对于无缝隙试样均有明显降低。
316 stainless steel pate was paired face by face with four plates of different materials respectively,i.e.316 SS,tetrafluoroethylene,rubber and plastic,and then the crevice corrosion behavior of the 316 SS for the above four pairs was assessed via immersion test in FeCl3 solution,while the relevant electrochemical performance was examined in an artificial seawater.After corrosion test,the samples were examined by laser confocal microscopy.Results show that among others,the pair 316 SS/316 SS presented the widest corrosion area with the most shallow depth,indicating that the corrosion pits tended to spread preferentially sideways.When the corrosion pits reach a certain depth,the lateral migration of corrosive solution got easier.The corrosion morphology of the pair 316 SS/rubber showed the minimum width with the maximum depth,suggesting the longitudinal development of the corrosion pit,which is related to the stress applied on the rubber.In that case,the corrosive medium is closely attached to the steel surface,hence hard to migrate laterally into the gab,thereby the corrosion expanded vertically in depth.Furthermore,the relevant mechanisum of crevice corrosion for different type of pairings was analyzed through electrochemical measurements.
作者
赵柏杰
范益
李镇镇
张博威
程学群
ZHAO Baijie;FAN Yi;LI Zhenzhen;ZHANG Bowei;CHENG Xuequn(Jiangsu Key Laboratory for Premium Steel Materials,Nanjing Iron&Steel United Co.,Ltd.,Nanjing 210035,China;Key Laboratory for Corrosion and Protection(MOE),Institute for Advanced Materials and Technology,University of Science and Technology Beijing,Beijing 100083,China)
出处
《中国腐蚀与防护学报》
CAS
CSCD
北大核心
2020年第4期332-341,共10页
Journal of Chinese Society For Corrosion and Protection
基金
国家自然科学基金青年科学基金(51901018)
中国博士后科学基金(2019M660456)
中央高校基本科研业务费(06500119)。
关键词
缝隙腐蚀
不锈钢
接触面
浸泡
crevice corrosion
stainless steel
contact surface
immersion
