Abstract
A nonlinear version of Wagner’s classical model of internal oxidation is presented. This version accounts for the fact that precipitates may act as diffusion barriers by introducing a heuristic dependence of the diffusion coefficients of elements upon the local volume fraction of oxides formed. Remarkably, the now nonlinear problem still admits an analytic solution. This solution reveals a sudden and discontinuous transition from internal oxidation to formation of some external oxidized scale, when the fraction of oxide precipitates reaches some critical value which can be calculated explicitly in terms of the respective specific volumes of the matrix and the oxide.
Similar content being viewed by others
Notes
The slight dependence of the former volume upon the dissolved fraction of element A is neglected.
The fact that successive estimates of P and D O are constant in space and time is the key feature that allows for an analytic solution to be found to the nonlinear problem. Of course, it is a consequence of the (often wrong in practice!) assumption made by Wagner that the solubility product of the precipitate is vanishingly small.
It is worth noting incidentally that these qualitative predictions are supported by Brunac et al.’s [1] finite difference simulations of diffusion of O and Al and precipitation of Al2O3 in a Fe matrix, based on the model discussed.
This does not remain true for the critical nominal concentration of the oxidizable element, since the diffusion coefficients enter the relation connecting the two critical quantities.
References
J. B. Brunac, D. Huin, and J. B. Leblond, Oxidation of Metals 73, 565 (2010).
H. J. Christ, H. G. Sockel, and W. Christl, Werkstoffe und Korrosion 37, 385–390 (1986) (German).
D. L. Douglass, Oxidation of Metals 44, 81 (1995).
F. Gesmundo and B. Gleeson, Oxidation of Metals 44, 211 (1995).
F. Gesmundo F and Y Niu, Oxidation of Metals 51, 129 (1999).
F. Gesmundo, F. Viani, and Y. Niu, Oxidation of Metals 45, 51 (1996).
F. Gesmundo, F. Viani, and Y. Niu, Oxidation of Metals 47, 355 (1997).
F. Gesmundo, P. Castello, F. Viani, and C. Roos, Oxidation of Metals 49, 237 (1998).
D. Huin, V. Lanteri, D. Loison, P. Autesserre, and H. Gaye, in Microscopy of Oxidation—3, eds. S. B. Newcomb and J. A. Little (The Institute of Metals, London, 1997), pp. 573.
J. S. Kirkaldy, Canadian Metallurgical Quarterly 8, 35 (1969).
J. S. Kirkaldy, in Oxidation of Metals and Alloys, ed. D. L. Douglass (American Society of Metals, Metals Park, 1971), pp. 101.
G. Laflamme and J. E. Morral, Acta Metallurgica 26, 1791 (1978).
Y. Niu and F. Gesmundo, Oxidation of Metals 56, 517 (2001).
E. K. Ohriner and J. E. Morral, Scripta Metallurgica 13, 7 (1979).
R. A. Rapp, Acta Metallurgica 9, 730 (1961).
R. A. Rapp, Corrosion 21, 382 (1965).
F. H. Stott and G. C. Wood, Materials Science and Technology 4, 1072 (1988).
C. Wagner, Zeitschrift für Elektrochemie 63, 772–782 (1959) (German).
D. P. Whittle, F. Gesmundo, B. D. Bastow, and G. C. Wood, Oxidation of Metals 16, 159 (1981).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Leblond, JB. A Note on a Nonlinear Version of Wagner’s Classical Model of Internal Oxidation. Oxid Met 75, 93–101 (2011). https://doi.org/10.1007/s11085-010-9222-6
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11085-010-9222-6