A flow model of porous anodic film growth on aluminium

Garcia-Vergara, S.J.; Skeldon, P.; Thompson, G.E.; Habazaki, H.

doi:10.1016/j.electacta.2006.05.054

Cited by 368 publications

(375 citation statements)

References 30 publications

Supporting

Mentioning

346

Contrasting

Unclassified

Order By: Relevance

“…Volume expansion of the oxide and fluoride may result in the plastic flow, which pushes the fluoride-rich layer upwards. Such a model was suggested by Garcia-Vergara et al [28]. It is the beginning of the tube formation.…”

Section: The Transfer Of Timentioning

confidence: 99%

Electrochemical synthesis of oxide nanotubes on Ti6Al7Nb alloy and their interaction with the simulated body fluid

Stępień

Handzlik

Fitzner

2016

J Solid State Electrochem

View full text Add to dashboard Cite

The aim of the present work was to investigate electrochemical behavior of the Ti6Al7Nb alloy in the simulated body fluid (SBF) containing Ca 2+ , HCO 3 − , and HPO 4 2 − ions. At first, optimal conditions necessary for oxide nanotube formation were determined. The experiments were conducted in the 1 M (NH 4 ) 2 SO 4 with 0.5 wt% NH 4 F electrolyte at room temperature. Anodization of the alloy samples was carried out under variable external voltage U in the range from 10 to 40 V at room temperature. Obtained surface morphology was examined by SEM and X-ray techniques. Nanotube diameter was calculated and correlated with the imposed voltage. Having control over the size of nanotubes, samples with the obtained nanostructures of a chosen diameter were immersed into SBF solution with pH = 7.4 for a fixed period of time. Then, they were removed from the fluid and subjected to the electrochemical investigation. Corrosion current and corrosion potential were determined, and it was found that the best anticorrosion properties were obtained for heat-treated nanotube layer: i corr = 39 nA/cm 2 and E corr = −0.236 V vs Ag/AgCl. Finally, the interaction between the oxide surface and the solution was studied using polarization and electrochemical impedance spectroscopy (EIS) techniques.

show abstract

Section: The Transfer Of Timentioning

confidence: 99%

Electrochemical synthesis of oxide nanotubes on Ti6Al7Nb alloy and their interaction with the simulated body fluid

Stępień

Handzlik

Fitzner

2016

J Solid State Electrochem

View full text Add to dashboard Cite

show abstract

“…The formation of the oxide mound is due to a high value of the Pilling-Bedworth ratio, R pb , during re-anodizing, defined as the ratio of the volumes of oxide formed and the metal substrate consumed in oxidation. The R pb depends on the anodizing conditions, showing R pb = 1.2 -1.65 in the formation of porous anodic oxide film by anodizing in acid solution [34]. This is the case in the present investigation, and the formation of the oxide mound can be explained as the result of an expansion of the specimen volume.…”

Section: Growth Of Porous Type Oxide Films After Laser Irradiationmentioning

confidence: 49%

Growth of porous type anodic oxide films at micro-areas on aluminum exposed by laser irradiation

Kikuchi

Sakairi

Takahashi

2009

Electrochimica Acta

View full text Add to dashboard Cite

Aluminum covered with pore-sealed anodic oxide films was irradiated with a pulsed Nd-YAG laser to remove the oxide film at micro-areas. The specimen was re-anodized for long periods to examine the growth of porous anodic oxide films at the area where substrate had been exposed by measuring current variations and morphological changes in the oxide during the re-anodizing. The chemical dissolution resistance of the pore-sealed anodic oxide films in an oxalic acid solution was also examined by measuring time-variations in rest potentials during immersion.The resistance to chemical dissolution of the oxide film became higher with increasing pore-sealing time and showed higher values at lower solution temperatures. During potentiostatic re-anodizing at five 35-µm wide and 4-mm long lines for 72 h after the film was removed the measured current was found to increase linearly with time. Semicircular columnar shaped porous type anodic oxide was found to form during the re-anodizing at the laser-irradiated area, and was found to grow radially, thus resulting in an increase in the diameter. After long re-anodizing, the central and top parts of the oxide protruded along the longitudinal direction of the laser-irradiated area. The volume expansion during re-anodizing resulted in the formation of cracks, parallel to the lines, in the oxide film formed during the first anodizing.

show abstract

“…The present study also reveals that chemical during anodizing of aluminium in aqueous acid electrolytes, i.e., 25 V in sulphuric acid [21], 40 V in oxalic acid [22] and 195 V in phosphoric acid [23]. In the present organic electrolytes, an optimized formation voltage appears to be present for the growth the ordered porous films, which should be between 30 and 50 V. The mechanism of self-ordering of pores in porous anodic films on metals is not yet understood and is the subject of further studies, although some models, including a stress-induced flow of film materials from a pore base to a pore wall, have recently been proposed [18,[24][25][26].…”

Section: Discussionmentioning

confidence: 99%

“…However, the enrichment was only obvious at lower H 2 O concentrations, at which the formation voltage increased to higher than 100 V [8]. The H 2 O concentration-dependent enrichment of fluoride may be related to the mechanism of porous film growth, i.e., either field-assisted dissolution [17] or field-assisted flow [18,19]. The precise understanding of the growth mechanism is the subject of further study.…”

Section: Methodsmentioning

confidence: 99%

Factors influencing the growth behaviour of nanoporous anodic films on iron under galvanostatic anodizing

Konno

Tsuji

Skeldon

et al. 2012

J Solid State Electrochem

Self Cite

View full text Add to dashboard Cite

show abstract

A flow model of porous anodic film growth on aluminium

Cited by 368 publications

References 30 publications

Electrochemical synthesis of oxide nanotubes on Ti6Al7Nb alloy and their interaction with the simulated body fluid

Electrochemical synthesis of oxide nanotubes on Ti6Al7Nb alloy and their interaction with the simulated body fluid

Growth of porous type anodic oxide films at micro-areas on aluminum exposed by laser irradiation

Factors influencing the growth behaviour of nanoporous anodic films on iron under galvanostatic anodizing

Contact Info

Product

Resources

About