Lowering of Initial Anodizing Current Density due to Thin Aluminum Oxide Film on Evaporated Aluminum

The strength of deposited film and the adhesion between the film and the substrate were investigated with deposited aluminum oxide film on iron surface by scratching the surface with a diamond cone. Two types of samples were examined, one with oxide film deposited after cleaning the substrate surface by sputter etching, the other with the film deposited without any sputter etching. It was found that a law similar to Meyers’ for indentation hardness holds between the load and scratch width on the sample examined. These results suggest that by analyzing the scratch data the adhesion strength of the film to the substrate can be estimated together with the hardness of the film itself. Analyses by EPMA (electron probe X-ray microanalyzer) and AES (Auger electron spectroscopy) were conducted to correlate the results obtained by the scratch tests and friction experiments, and it was confirmed that (i) adhesion is improved by sputter etching prior to the deposition of the film; (ii) adhesion decreases considerably due to the progress of oxidation in the vicinity of the interface, which depends markedly on the oxygen concentration in the oxide film; and (iii) there is an optimum thickness of the three-component layer (Fe, Al, and O) formed by atomic mixing at the interface for maximizing the adhesion.

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Anodic Current Density of Aluminum Oxide Film in Situ during Anodization of Aluminum by Fabry-Pérot Interferometry

ECS Meeting Abstracts ◽

10.1149/ma2018-02/14/674 ◽

2018 ◽

Keyword(s):

Oxide Film ◽

Aluminum Oxide ◽

Current Density ◽

Anodic Current Density ◽

Anodic Current ◽

Aluminum Oxide Film ◽

Fabry Perot

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The structure of Pt-aggregates on a supported thin aluminum oxide film in comparison with unsupported alumina: a transmission electron microscopy study

Surface Science ◽

10.1016/s0039-6028(97)00449-4 ◽

1997 ◽

Vol 391 (1-3) ◽

pp. 27-36 ◽

Cited By ~ 75

Author(s):

M. Klimenkov ◽

S. Nepijko ◽

H. Kuhlenbeck ◽

M. Bäumer ◽

R. Schlögl ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Oxide Film ◽

Aluminum Oxide ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Transmission Electron Microscopy Study ◽

Aluminum Oxide Film ◽

Transmission Electron ◽

Thin Aluminum

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Peculiar Porous Aluminum Oxide Films Produced viaElectrochemical Anodizing in Malonic Acid Solution withArsenazo-I Additive

Materials ◽

10.3390/ma14175118 ◽

2021 ◽

Vol 14 (17) ◽

pp. 5118

Author(s):

Alexander Poznyak ◽

Gerhard Knörnschild ◽

Anatoly Karoza ◽

Małgorzata Norek ◽

Andrei Pligovka

Keyword(s):

Oxide Film ◽

Aluminum Oxide ◽

Malonic Acid ◽

Current Density ◽

Pure Aluminum ◽

Film Structure ◽

Hydroxyl Groups ◽

Porous Aluminum ◽

Aluminum Oxide Film ◽

Porous Aluminum Oxide

The influence of arsenazo-I additive on electrochemical anodizing of pure aluminum foil in malonic acid was studied. Aluminum dissolution increased with increasing arsenazo-I concentration. The addition of arsenazo-I also led to an increase in the volume expansion factor up to 2.3 due to the incorporation of organic compounds and an increased number of hydroxyl groups in the porous aluminum oxide film. At a current density of 15 mA·cm–2 and an arsenazo-I concentration 3.5 g·L–1, the carbon content in the anodic alumina of 49 at. % was achieved. An increase in the current density and concentration of arsenazo-I caused the formation of an arsenic-containing compound with the formula Na1,5Al2(OH)4,5(AsO4)3·7H2O in the porous aluminum oxide film phase. These film modifications cause a higher number of defects and, thus, increase the ionic conductivity, leading to a reduced electric field in galvanostatic anodizing tests. A self-adjusting growth mechanism, which leads to a higher degree of self-ordering in the arsenazo-free electrolyte, is not operative under the same conditions when arsenazo-I is added. Instead, a dielectric breakdown mechanism was observed, which caused the disordered porous aluminum oxide film structure.

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Charge decay in amorphous selenium layers with an intermediate aluminum oxide film

Canadian Journal of Physics ◽

10.1139/p91-047 ◽

1991 ◽

Vol 69 (3-4) ◽

pp. 278-283 ◽

Cited By ~ 7

Author(s):

Qi-Hua Zhang ◽

C. H. Champness

Keyword(s):

Glow Discharge ◽

Oxide Film ◽

Aluminum Oxide ◽

Thermal Oxidation ◽

Low Voltage ◽

Amorphous Selenium ◽

Aluminum Oxide Film ◽

Thin Aluminum ◽

Charge Decay ◽

Dark Decay

Amorphous selenium is often used as the basic photoreceptor material in xerography in the form of a layer on an aluminum substrate. It is found that the dark decay rate of charge on the selenium surface can be reduced by the presence of a thin aluminum oxide film between the selenium and the substrate metal. In this study, different methods were explored for forming this film, including direct thermal oxidation and various glow-discharge methods. It was found that with thermal oxidation and low voltage glow discharge, the film thicknesses were limited to about 200 Å (1 Å = 10−10 m). However, with dc reactive sputtering, aluminum oxide films with thicknesses of more than 2000 Å could be prepared. Evaluation of the films, with the selenium layer present, indicated that the low voltage glow-discharge and direct thermal oxidation methods gave the best results xerographically.

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