High temperature oxidation of metals ? Study guide

Dry corrosion is the degradation of a material in a chemically reactive environment due to high temperatures and, in some cases, mechanical stress.

It generally pertains to advanced technological fields where the consequences of failures entail particularly high financial, environmental, or human costs: thermal machinery for transportation (land, sea, and air), energy conversion, the nuclear industry, the chemical industry (organic and inorganic), metallurgy...

The specifications for metallic materials used in these fields are becoming increasingly demanding. Operating temperatures are being raised to improve efficiency. Cost reduction and environmental concerns are driving the selection of high-performance materials with the thinnest possible wall thickness. Finally, safety requirements necessitate the ability to guarantee a service life under operating conditions, whether in terms of creep, microstructural stability, or high-temperature oxidation.

There is therefore a strong demand for quantitative data on the behavior of materials subjected to dry corrosion. This demand encompasses reaction rates, maximum operating temperatures, prohibited atmospheres, thermal cycling conditions, and mechanical stresses during service.

The analysis of dry corrosion phenomena is multidisciplinary in nature, as it requires expertise in metallurgy, surface science, thermodynamics and chemical kinetics, and solid-state chemistry and physics.

The first section of this article introduces the phenomenon of dry corrosion and its specific characteristics: how it differs from aqueous corrosion, the temperatures and atmospheres in which it occurs, and the industrial sectors affected. The second section outlines a research approach, ranging from the implementation of thermogravimetric monitoring experiments to the chemical, morphological, and mechanical characterization of the corrosion layer and its interface with the metal.