{"title":"An ellipsometric, XPS and electrochemical study of the passivity of zircaloy-2","authors":"S. Phadnis, A. Bose, M. Totlani","doi":"10.1080/00202967.1999.11871283","DOIUrl":null,"url":null,"abstract":"The electrochemical behaviour of zircaloy-2 in the annealed and quenched conditions was determined in 0.5 M H 2 SO 4 by the potentiodynamic polarization method. Passive films on zircaloy-2 obtained in air as well as in sulphuric acid under open circuit conditions, were characterised and their refractive index and thickness determined. It was seen that the beta quenched alloy showed a nobler potential (-270 mV against standard Calomel electrode) compared with the annealed alloy (-320 mV). It also showed a passive current density about one order less than the annealed material. Ellipsometry showed that the films formed on the quenched alloy were thinner than those on the annealed alloy. After exposure to 0.5 M H 2 SO 4 zircaloy developed films which were thicker with power refractive index than both the heat treated conditions. XPS analysis of the films has confirmed incorporation of sulphate into the film which probably leads to a defective and hence a thicker film in acid.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":"77 1","pages":"200-203"},"PeriodicalIF":1.2000,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1999.11871283","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Transactions of The Institute of Metal Finishing","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1080/00202967.1999.11871283","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ELECTROCHEMISTRY","Score":null,"Total":0}
引用次数: 0
Abstract
The electrochemical behaviour of zircaloy-2 in the annealed and quenched conditions was determined in 0.5 M H 2 SO 4 by the potentiodynamic polarization method. Passive films on zircaloy-2 obtained in air as well as in sulphuric acid under open circuit conditions, were characterised and their refractive index and thickness determined. It was seen that the beta quenched alloy showed a nobler potential (-270 mV against standard Calomel electrode) compared with the annealed alloy (-320 mV). It also showed a passive current density about one order less than the annealed material. Ellipsometry showed that the films formed on the quenched alloy were thinner than those on the annealed alloy. After exposure to 0.5 M H 2 SO 4 zircaloy developed films which were thicker with power refractive index than both the heat treated conditions. XPS analysis of the films has confirmed incorporation of sulphate into the film which probably leads to a defective and hence a thicker film in acid.
用动电位极化法测定了锆-2在0.5 M h2so4中退火和淬火条件下的电化学行为。在开路条件下,在空气和硫酸中制备了锆-2钝化膜,对其进行了表征,并测定了其折射率和厚度。与退火合金(-320 mV)相比,淬火合金表现出更高的电位(对标准甘汞电极为-270 mV)。它的无源电流密度也比退火后的材料小一个数量级。椭偏测量结果表明,淬火合金表面形成的薄膜比退火合金表面薄。暴露于0.5 M h2so4后,锆合金形成的薄膜比两种热处理条件下的薄膜更厚,其功率折射率也更高。薄膜的XPS分析证实了硫酸盐在薄膜中的掺入,这可能导致了缺陷,因此在酸中形成了较厚的薄膜。
期刊介绍:
Transactions of the Institute of Metal Finishing provides international peer-reviewed coverage of all aspects of surface finishing and surface engineering, from fundamental research to in-service applications. The coverage is principally concerned with the application of surface engineering and coating technologies to enhance the properties of engineering components and assemblies. These techniques include electroplating and electroless plating and their pre- and post-treatments, thus embracing all cleaning pickling and chemical conversion processes, and also complementary processes such as anodising. Increasingly, other processes are becoming important particularly regarding surface profile, texture, opacity, contact integrity, etc.