首页 | 本学科首页   官方微博 | 高级检索  
     


Electrochemical impedance spectroscopy and linear polarization applied to evaluation of porosity of phosphate conversion coatings on electrogalvanized steels
Authors:Vanessa de Freitas Cunha Lins  Geraldo Francisco de Andrade Reis  Carlos Roberto de Araujo
Affiliation:a Corrosion and Surface Engineering Laboratory, Chemical Engineering Department, Federal University of Minas Gerais, Rua Espirito Santo 35, 6th floor, Belo Horizonte 30160-030, Brazil
b Chemical Department, Federal University of Minas Gerais, AV. Antonio Carlos, 6627-Pampulha, Belo Horizonte 31270-901, Brazil
Abstract:
In this work, electrochemical impedance spectroscopy and linear polarization are used in determining porosity of zinc phosphates, and of nickel and manganese modified zinc phosphates on electrogalvanized steel. The porosity of the phosphate layers ranges from 0.1% for the manganese-modified hopeite to 8% for hopeite, using the linear polarization and the electrochemical impedance spectroscopy techniques. The porosity values measured using the two techniques were in agreement. All impedance spectra of coated samples showed two steps, with two capacitive arcs and an inductive looping.
Keywords:Phosphate conversion coatings   Electrochemical impedance spectroscopy   Porosity   Linear polarization
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号