Thin Al2O3 Coatings Produced by Electrochemical Method, Subjected to Thermo-Chemical Treatment

The article presents the effect of the anodizing parameters, as well as the thermo-chemical treatment, of Al2O3 layers produced on an aluminum alloy on the characterization of structure, geometrical structure of the surface (SGS), the thickness of the oxide layers, the phase composition, and their microhardness. The oxide layers were produced by the method of direct current anodizing in a three-component electrolyte. Then, thermo-chemical treatment was carried out in distilled water and aqueous solutions of sodium dichromate and sodium sulphate. The anodizing parameters and compounds for the thermo-chemical treatment were selected on the basis of Hartley’s plans. The research showed the effect of anodizing parameters on the thickness of the Al2O3 layers and the increase in the thickness of the layers as a result of the thermo-chemical treatment. The research showed a significant increase in the microhardness of the layers as a result of thermo-chemical treatment and its influence on the phase composition of Al2O3 layers. A significant influence of the thermo-chemical treatment on the geometrical structure of the surface was also found.

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Effects of pH, surface finish and thermal treatment on the corrosion of AlFeNi aluminum alloy. Characterization of oxide layers

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2014.10.023 ◽

2015 ◽

Vol 457 ◽

pp. 196-204 ◽

Cited By ~ 4

Author(s):

D. Nabhan ◽

B. Kapusta ◽

P. Billaud ◽

K. Colas ◽

D. Hamon ◽

...

Keyword(s):

Aluminum Alloy ◽

Thermal Treatment ◽

Surface Finish ◽

Oxide Layers ◽

Effects Of Ph

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Synthesis And Characterization Of Nine Metal Nitrides

MRS Proceedings ◽

10.1557/proc-410-121 ◽

1995 ◽

Vol 410 ◽

Cited By ~ 2

Author(s):

Travis Wade ◽

Richard M. Crooks

Keyword(s):

Phase Composition ◽

Electrochemical Method ◽

Ceramic Materials ◽

Synthesis And Characterization ◽

Metal Nitrides ◽

Ceramic Powders ◽

Metal Nitride ◽

Nitride Ceramics ◽

Precursor Powders

ABSTRACTWe demonstrate a simple electrochemical method suitable for preparing precursors for nine different metal-nitride ceramics. These precursor powders were calcined in flowing NH3 or Ar to yield metal-nitride ceramic powders. This electrochemical synthetic technique was applied to Al, Ga, Mo, Nb, Ni, Ti, V, W, and Zr and resulted in a nitride of each of these metals. The calcination conditions determined the resulting phase, composition, and morphology of the product. The ceramic materials were characterized primarily by powder XRD.

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CHARACTERIZATION OF OXIDE LAYERS MADE ON ALUMINUM ALLOY 7075 BY DIFFERENT METHODS

Metallurgy and Foundry Engineering ◽

10.7494/mafe.2016.42.3.187 ◽

2016 ◽

Vol 42 (3) ◽

pp. 187

Author(s):

Mateusz Jędrusik ◽

Aleksandra Dębowska ◽

Agnieszka Kopia ◽

Paweł Petrzak ◽

Damian Koclęga ◽

...

Keyword(s):

Aluminum Alloy ◽

Oxide Layers ◽

Aluminum Alloy 7075

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Microestructural characterization of a asymmetric accumulative roll bonded (AARB) of AA1050 aluminum alloy

10.26678/abcm.cobef2017.cof2017-1132 ◽

2017 ◽

Author(s):

Renan Godoi ◽

Felipe Almeida ◽

Andrea Madeira Kliauga

Keyword(s):

Aluminum Alloy

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THE EFFECT OF ELECTROLYTE TEMPERATURE AND SEALING SOLUTION IN ANODIZING OPERATION ON HARDNESS AND WEAR BEHAVIOR OF 7075 -T6 ALUMINUM ALLOY

Surface Review and Letters ◽

10.1142/s0218625x18501433 ◽

2019 ◽

Vol 26 (02) ◽

pp. 1850143

Author(s):

SAEED NIYAZBAKHSH ◽

KAMRAN AMINI ◽

FARHAD GHARAVI

Keyword(s):

Weight Loss ◽

Wear Resistance ◽

Aluminum Alloy ◽

Wear Behavior ◽

Anodic Oxide ◽

Boiling Water ◽

Electrolyte Temperature ◽

Oxide Coatings ◽

Sodium Dichromate ◽

Pin On Disk

Anodic oxide coatings are applied on aluminum alloys in order to improve corrosion resistance and to increase hardness and wear resistance. In the current study, a hard anodic coating was applied on AA7075-T6 aluminum alloy. To survey the anodizing temperature (electrolyte temperature) effect, three temperatures, namely, [Formula: see text]C, 0∘C and 5∘C were chosen and the samples were sealed in boiling water and sodium dichromate to study the role of sealing. For measuring the oxide coatings porosity and hardness and also for comparing the samples’ wear resistance field-emission scanning electron microscopy (FESEM), microhardness test and pin-on-disk method were utilized, respectively. The results showed that by increasing the anodizing temperature, hardness and consequently wear resistance decreased so that hardness and weight loss in the samples with no sealing decreased from 460[Formula: see text]HV and 0.61[Formula: see text]mg at [Formula: see text]C to 405 and 358[Formula: see text]HV and 1.05 and 1.12[Formula: see text]mg at 0∘C and 5∘C, respectively, which is due to the porosity increment by increasing the anodizing temperature. Also, sealing in boiling water and dichromate contributed to soft phases and coating hydration, which resulted in a decrease in hardness and wear resistance. Hardness and weight loss in the coated samples at [Formula: see text]C decreased from 460[Formula: see text]HV and 0.61[Formula: see text]mg in the samples with no sealing to 435 and 417[Formula: see text]HV and 0.72 and 0.83[Formula: see text]mg in the samples sealed in boiling water and dichromate, respectively.

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