Oxidation of metal alloys

Let us now compare the internal oxidation of nonmetallic (oxide) solid solutions with the internal oxidation of metal alloys. The role of the (neutral) point defect... 

Atwood, D. A. 2004. Compositions and Methods for Reducing Oxidation of Metal Alloys During Heating. U. S. Utility Patent Application. 

The discussion of Section 17.2 treated the corrosion of metallic materials in terms of electrochemical reactions that take place in aqueous solutions. In addition, oxidation of metal alloys is also possible in gaseous atmospheres, normally air, in which an oxide layer or scale forms on the surface of the metal. This phenomenon is frequently termed scaling, tarnishing, or dry corrosion. In this section, we discuss possible mechanisms for this type of corrosion, the types of oxide layers that can form, and the kinetics of oxide formation. 

O. Kubaschewski and B. E. Hopkins, Oxidation of Metals and Alloys, 2nd edition, Butterworths, 1962. 

Benard, J., Adsorption of Oxidant and Oxide Nucleation , in Oxidation of Metals and Alloys, Seminar, 1970 American Society for Metals, Ohio, 1 (1971)... 

Kofsted, P., High Temperature Oxidation of Metals, John Wiley, New York 0965) Kubaschewski, O. and Hopkins, B. F., Oxidation of Metals and Alloys, Butterworths, London... 

Manly, W. D.etai., Proceedings of the Second Conference on the Peaceful Uses of Atomic Energy, United Nations, Geneva, 1958, Pub. No. A/CONF/15/P/1990 Evans, U. R., The Corrosion and Oxidation of metals, Arnold, London, 356-357 (1960) Jackson, J, H., Alloy Cast. Bull., No. 16, 1 (1952)... 

Whether the rate of oxidation of an alloy of copper with a baser metal is less or more than that of copper will depend on the concentration of the alloying element and the relative diffusion velocities of metal atoms or ions in the oxide layers. There is extensive literature on the oxidation behaviour of copper alloys According to Wagner s theory the rate of oxida-... 

The more fundamental aspects of the oxidation of metals have been fully described in Chapter 1, and by Kubaschewski and Hopkins , while practical considerations, particularly in relation to commercially important alloys, have been dealt with by Hessenbruch. ... 

Table 7.6 Effect of various gases on the oxidation of metals and alloy steels (gains in gm d )...

Data after Kubaschewski and Hopkins, The Oxidation of Metals and Alloys, Butterworths. London (1962). 

The raw materials needed to supply about ten million new automobiles a year do not impose a difficult problem except in the case of the noble metals. Present technology indicates that each car may need up to ten pounds of pellets, two pounds of monoliths, or two pounds of metal alloys. The refractory oxide support materials are usually a mixture of silica, alumina, magnesia, lithium oxide, and zirconium oxide. Fifty thousand tons of such materials a year do not raise serious problems (47). The base metal oxides requirement per car may be 0.1 to 1 lb per car, or up to five thousand tons a year. The current U.S. annual consumption of copper, manganese, and chromium is above a million tons per year, and the consumption of nickel and tungsten above a hundred thousand tons per year. The only important metals used at the low rate of five thousand tons per year are cobalt, vanadium, and the rare earths. 

Corrosion is essentially an electrochemical process, wherein the oxidation of metals or alloys to their (lower energy state) oxides or cations takes place. 

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