Abstract
This work tackles the aqueous chemistry of Zr, aiming to contribute to a better understanding of Zr conversion coatings as one of the important contemporary means of corrosion protection. Equilibrium predominance diagrams based on experimentally confirmed Zr–OH and Zr–F aqueous species concerning Zr amorphous solid phase, along with an updated ZrE−pH (Pourbaix) diagram, are constructed. Since ZrO2+existence had been conclusively disproven in both the aqueous and solid states, we chose to depict mononuclear species with ZrOH3+and polynuclear with Zr4(OH)88+. The formation of the Zr solid phase is assumed to include Zr tetrameric species, Zr4(OH)88+, as a fundamental building block thereof. The role of F–and ZrF62–ions in Zr conversion baths and subsequently formed coatings is described. The introduction of ZrF62–anions keeps Zr solvated in the form of a complex, thus preventing the early onset of hydrolysis. The conversion of Zr species and the coating formation mechanism are further discussed from electrochemical and sol-gel perspectives, aiming to give a foundation for future predictions and rationalisation of Zr conversion coating formation, with the possibility of extensions to various bath additives.
Funder
Javna Agencija za Raziskovalno Dejavnost RS
Publisher
The Electrochemical Society
Subject
Materials Chemistry,Electrochemistry,Surfaces, Coatings and Films,Condensed Matter Physics,Renewable Energy, Sustainability and the Environment,Electronic, Optical and Magnetic Materials
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献