Oxidation modelling of a Si3N4–TiN ceramic: microstructure and kinetic laws

Abstract : The oxidation of a silicon nitride–titanium nitride ceramic has been studied. Based on microstructural observations, a phenomenological oxidation model is described, and an oxidation kinetic model has been proposed. For temperatures <1000 °C, only the TiN phase is oxidised. The oxidation process is then controlled by oxygen diffusion through TiO2, described by a parabolic oxidation kinetic law. The process is more complex above 1000 °C, because of the simultaneous oxidation of both Si3N4 and TiN phases. Three oxidation modes, controlled by distinct diffusion mechanisms, take place successively. In a first step, Si3N4 and TiN phases are independently oxidised, respectively into SiO2 and TiO2 phases. Si3N4 oxidation is controlled by oxygen diffusion through SiO2, while TiN oxidation is controlled by titanium diffusion through TiO2. In a second step, the TiN oxidation is controlled by oxygen diffusion through TiO2 and through SiO2 formed by Si3N4 oxidation. In the third step, oxidation of the TiN and Si3N4 phases is controlled by oxygen diffusion through the silica layer. Kinetic laws have been proposed for each of these three oxidation modes.
Type de document :
Article dans une revue
Ceramics International, Elsevier, 2007, 33, pp.1331-1339. 〈10.1016/j.ceramint.2006.04.016〉
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https://hal.archives-ouvertes.fr/hal-00170659
Contributeur : Odile Adam <>
Soumis le : lundi 10 septembre 2007 - 12:01:47
Dernière modification le : lundi 12 novembre 2018 - 11:05:45

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Frédéric Deschaux-Beaume, Nicole Fréty, Thierry Cutard, Christophe Colin. Oxidation modelling of a Si3N4–TiN ceramic: microstructure and kinetic laws. Ceramics International, Elsevier, 2007, 33, pp.1331-1339. 〈10.1016/j.ceramint.2006.04.016〉. 〈hal-00170659〉

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