Influence of frequency on the structure of zirconium oxide coatings deposited from aqueous electrolytes under microplasma oxidation

2015 ◽  
Author(s):  
Tatiana A. Gubaidulina ◽  
Viktor P. Sergeev ◽  
Oleg S. Kuzmin ◽  
Marina V. Fedorischeva ◽  
Mark P. Kalashnikov
Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1043
Author(s):  
Vitor Bonamigo Moreira ◽  
Anna Puiggalí-Jou ◽  
Emilio Jiménez-Piqué ◽  
Carlos Alemán ◽  
Alvaro Meneguzzi ◽  
...  

Herein, the influence of the substrate in the formation of zirconium oxide monolayer, from an aqueous hexafluorozirconic acid solution, by chemical conversion and by electro-assisted deposition, has been approached. The nanoscale dimensions of the ZrO2 film is affected by the substrate nature and roughness. This study evidenced that the mechanism of Zr-EAD is dependent on the potential applied and on the substrate composition, whereas conversion coating is uniquely dependent on the adsorption reaction time. The zirconium oxide based nanofilms were more homogenous in AA2024 substrates if compared to pure Al grade (AA1100). It was justified by the high content of Cu alloying element present in the grain boundaries of the latter. Such intermetallic active sites favor the obtaining of ZrO2 films, as demonstrated by XPS and AFM results. From a mechanistic point of view, the electrochemical reactions take place simultaneously with the conventional chemical conversion process driven by ions diffusion. Such findings will bring new perspectives for the generation of controlled oxide coatings in modified electrodes used, as for example, in the construction of battery cells; in automotive and in aerospace industries, to replace micrometric layers of zinc phosphate by light-weight zirconium oxide nanometric ones. This study is particularly addressed for the reduction of industrial waste by applying green bath solutions without the need of auxiliary compounds and using lightweight ceramic materials.


2012 ◽  
Vol 445 ◽  
pp. 637-642 ◽  
Author(s):  
Y. Gencer ◽  
M. Tarakci ◽  
S. Cengiz ◽  
K.O. Gunduz

In this study, zirconium oxide coatings were formed on pure zirconium by microarc oxidation technique with the electrolytes containing KOH and different amounts of sodium silicate (0-40 gr/lt) for the same coating duration of 2 hours. The microstructure, surface roughness, phase content and chemical composition of the coatings were characterized by using scanning electron microscopy, profilometery and X-ray diffractometry. It was found that the coatings on surface of zirconium consist of monoclinic ZrO2 (m-ZrO2) and tetragonal ZrO2 (t-ZrO2) phases and the addition and increasing sodium silicate concentration in the electrolyte increases amount of t-ZrO2 phase. The coatings were well adhered to Zr substrate with some cracks and porosities in the coating for all concentrations of sodium silicate. The coating thickness and surface roughness increased with sodium silicate concentration in the electrolyte. A glaze like Si rich structure and its increase with Si rate was evident in the outermost region of the coating.


2004 ◽  
Vol 843 ◽  
Author(s):  
Jun C. Nable ◽  
Shaneela Nosheen ◽  
Steven L. Suib ◽  
Francis S. Galasso ◽  
Michael A. Kmetz

ABSTRACTInterface coatings on fibers are important in ceramic matrix composites. In addition to providing toughness, the interface coating must also protect the reinforcing ceramic fibers from corrosive degradation. A double interface coating has been applied onto silicon carbide fibers. The double interface coating is comprised of a combination of nitride and oxide coatings. Among the nitrides, boron nitride and titanium nitride were utilized. These nitrides were deposited by CVD. The metal oxides of choice were aluminum oxide and zirconium oxide which were applied onto the nitride coatings by MOCVD. The phases on the coated fibers were determined by XRD. The surface coating microstructures were observed by SEM. The effect of the coatings on the tensile strengths was determined by Instron tensile strength measurements.


2009 ◽  
Vol 517 (6) ◽  
pp. 1967-1969 ◽  
Author(s):  
R. Ugas-Carrión ◽  
F. Sittner ◽  
C.J. Ochs ◽  
S. Flege ◽  
W. Ensinger

Author(s):  
Kirsten Bobzin ◽  
Erich Lugscheider ◽  
Michel Maes ◽  
Philipp Immich

2013 ◽  
Vol 39 (8) ◽  
pp. 9665-9670 ◽  
Author(s):  
Y. Adraider ◽  
Y.X. Pang ◽  
F. Nabhani ◽  
S.N. Hodgson ◽  
M.C. Sharp ◽  
...  

2014 ◽  
Vol 3 (1) ◽  
Author(s):  
Olaf Stenzel

AbstractThe density of optical coatings is one of the most crucial material-related parameters in interference coating science and technology. It has an impact on the refractive index, the transparency range, and the mechanical stress of a coating material. This tutorial provides a background on the classical theory relating the coating density to the mentioned parameters. Simple models are presented that highlight the correlations between optical constants, stress, and shifting behavior of different oxide coatings. Comparison with the experiment is performed on the basis of numerous experimental data, which stem from hafnium oxide, zirconium oxide, tantalum pentoxide, and silicon dioxide.


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