Atmospheric corrosion behaviour

Ayoub, C., Davin, A., Goodwin, F. E., and Coutsouradis, D. (1988). Atmospheric corrosion behaviour of Galfan coated steels. 2nd Int. Conf. Zinc-Coated Steel Sheet, ZDA, London, pp. SA2/1-31. 

F. Mansfeld and R. Vijayakumar, Atmospheric corrosion behaviour in southern California, Corros. Sci. 28 939 (1988). 

Zoccola, J.C., H.E. Townsend, A.R. Borzillo and J.B. Horton, 1978, Atmospheric corrosion behaviour of Al-Zn alley coated steel, in Atmospheric Factors Affecting the Corrosion of Engineering Metals, ASTM STP 646, ed, S.K. Coburn (ASTM, Philadelphia, PA) pp, 165-184. 

The atmospheric corrosion of metals is largely dependent on the electrochemical reactions occurring in the thin aqueous layer on the surface and at the interface between the solid substrate and the thin electrolyte layer. The thin aqueous layer on the surface also acts as a conductive medium which can support electrochemical processes on the surface. Due to the presence of different phases with different electrochemical properties in magnesium alloys the anodic and cathodic reactions are often localised in different areas on the magnesium surface. The microelectrodes may consist of different phases present in the microstructure of the alloys. The influence of the microstructure on the atmospheric corrosion behaviour of magnesium alloys will be discussed in more detail further on. In atmospheric corrosion the thin electrolyte reduces... 

It is important to remember that the potential of the different constituents only shows the driving force of the process that is to take place, whereas nothing is said about the kinetics, which, as will be shown, are dependent on a number of factors. Usually potentiodynamic measurements are used to investigate the kinetics of an alloy and of synthetically prepared phases (51, 52, 58). However, as is the case when measuring the corrosion potential, potentiodynamic measurements also require a bulk electrolyte. To get a more comprehensive idea about the atmospheric corrosion behaviour, the surface itself needs to be studied and other techniques have to be utilised. 

Haynes G., Baboian R., Atmospheric corrosion behaviour of clad metal, ASTM, STP %5,1988, p. 145-190. 

In considering the corrosion behaviour of magnesium alloys, therefore, it is of the utmost importance to know the nature of the medium to which the metal is to be exposed. In general, atmospheric attack in damp conditions is largely superficial aqueous solutions bring about attack which varies not only with the solute but with the volume, movement and temperature... 

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. 

FZJ has adopted the design with stainless steel interconnect plates due to the steel s high electrical conductivity und the ensuing high power densities and compact stack designs. At the same time this material has a promising potential for low cost production. Still, the problems of chromium species evaporation from the steel and the corrosion behaviour of steel in SOFC relevant atmospheres need to be carefully addressed in order to achieve an... 

Baker, E. A. Long term corrosion behaviour of materials in the marine atmosphere, degradation of metals in the atmosphere, STP 965, ASTM, New Jersey 125-144 (1998)... 

Clarke, S. G., and Longhurst, E. E. (1962). The corrosion behaviour of metals and protective coatings in tropical atmosphere exposure tests. 1st Int. Congress on Metallic Corrosion, Butterworths, London, pp. 254-268. 

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