ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The formation of porous anodic films on FVS0812 aluminium alloy has been examined by transmission electron microscopy in order to elucidate the processes of film growth. A complex morphology of film material is revealed containing relatively tortuous, branched and terminated porosity and relatively large cavities. The morphology is associated with the differing anodic oxidation behaviour of the aluminium matrix and silicide dispersion regions of the alloy and the differing chemical stabilities of the resultant film regions. The anodic oxidation of the silicide proceeds more slowly than that of the aluminium matrix, with the production of film material of much finer morphology. The reduced rate of oxidation of the silicide is attributed to the effects of alloying element species in the anodic film material and pore solution. The rate of oxidation of the silicide is sufficient for most of the particles to be oxidized completely during anodizing. However, the resultant film material subsequently dissolves in the pore solution leaving relatively large cavities in the film. The differing oxidation rates of the alloy components, coupled with locally differing film properties, leads to a relatively rough alloy/film interface.© 1998 Kluwer Academic Publishers
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1004413521804
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