Aluminium alloys corrosion behaviour

Metals which owe their good corrosion resistance to the presence of thin, passive or protective surface films may be susceptible to pitting attack when the surface film breaks down locally and does not reform. Thus stainless steels, mild steels, aluminium alloys, and nickel and copper-base alloys (as well as many other less common alloys) may all be susceptible to pitting attack under certain environmental conditions, and pitting corrosion provides an excellent example of the way in which crystal defects of various kinds can affect the integrity of surface films and hence corrosion behaviour. 

Frazer, M. J. and Langstaff, R. D., Influence of Cupric Ions on the Behaviour of Surface-active Agents Towards Aluminium , Bril. Corrosion J., 2, II (1%7) Szklarska-Smialowska, Z. and Janik-Czachor, H., Pitting Corrosion of 13Cr-Fe Alloy in Na2S04 Solutions Containing Chloride Ions , Corros. Sci., 7, 65 (1967)... 

High Temperature Corrosion Behaviour of Iron Aluminides and Iron-Aluminium Chromium Alloys... 

While additions of mischmetal have a huge impact on the oxidation behaviour of iron-aluminium-chromium alloys, changes in the concentration of aluminium or chromium do not effect the corrosion behaviour significantly. The differences between the... 

The high temperature corrosion behaviour of different iron aluminides and iron-aluminium-chromium alloys containing 6-17 wt% aluminium, 2-10 wt% chromium and additions of mischmetal has been investigated in both air and hot process gases. 

In air, carburising atmospheres and sulphidising/oxidising atmospheres all alloys showed excellent corrosion resistance due to the formation of protective oxide scales. It was found that the concentration of aluminium or chromium does not significantly effect the corrosion behaviour in any of these environments. 10 wt% aluminium, probably even less, are sufficient to enable the formation of protective Al203-scales even at temperatures as low as 650°C. Overdoping with reactive elements (mischmetal), however, causes high oxidation rates in air and should be avoided. 

N.E. Idenyi, C.E. Ekuma (2006). The effects of zinc additions on the corrosion behaviour of aluminium alloy in saline environments. Journal of the Nigerian Environmental Society 3, p. 109. 

Some understanding of the corrosion of aluminium alloys used as cladding on research and test reactor fuel has been obtained from the CRP. Aluminium corrosion is extremely complex and the variables affecting localized corrosion (pitting and crevice corrosion) act both independently and synergistically. Additional information about the effects of deposited particle composition on the corrosion behaviour of aluminium alloys is needed. Surface finish affects the corrosion of aluminium alloys, and more information is required with respect to this parameter. Additional data on the effects of certain impurity ions in basin water on localized corrosion behaviour are necessary to better identify the ions that cause corrosion. A goal would be to develop an equation for pitting as a function of water chemistry parameters. 

These guidelines are for corrosion protection of the aluminium cladding, to prevent breach of this cladding and subsequent corrosion of the fuel core. Most research reactor fuel is fabricated from uranium-aluminium alloys, and this type of fuel exhibits corrosion behaviour similar to that of aluminium. Therefore implementation of these guidelines should also minimize corrosion of the fuel core. The corrosion of a metallic uranium core is much more rapid than that of a uranium-aluminium alloy core. Implementing the guidelines to protect aluminium cladding will also reduce the corrosion of this type of fuel core. 

CORROSION BEHAVIOUR OF ALUMINIUM ALLOYS IN THE SPENT FUEL STORAGE SECTION OF THE lEA-Rl RESEARCH REACTOR,... 

CORROSION BEHAVIOUR OF ALUMINIUM ALLOY TEST COUPONS IN THE SPENT FUEL BASIN OF THE CHINA INSTITUTE OF ATOMIC ENERGY, BEIJING... 

The main objectives of the programme were to provide comparative information about the corrosion behaviour of different types of aluminium alloy coupon in the IR-8 storage basin water. The following results were obtained ... 

The corrosion research programme could usefully be extended to investigate the influence of various surface treatments, for instance anodizing and preliminary autoclaving, on the corrosion behaviour of aluminium alloys. 

It is well known that the corrosion resistance of aluminium alloys can be improved by adding inhibitors to the aqueous environment. Consequently it would be worth evaluating the corrosion behaviour of aluminium alloys in the presence of inhibitors such as phosphates and chromates. 

Corrosion behaviour and protection of copper and aluminium alloys in seawater... 

Modi, O. P., Saxena, M., Prasad, B. K., Yegneswaran, A. H., and Vaidya, M. L., Corrosion Behaviour of Squeeze-Cast Aluminium Alloy—Silicon Carbide Composites, Journal of Materials Science, Vol. 27, 1992, pp. 3897-3902. 

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