Search results for "Solution solide"
showing 3 items of 3 documents
Influence of mass transport on the competition between corrosion of aluminium alloy surface and the release of primer containing inhibitors : validat…
2014
The conventional aircraft paint scheme for corrosion protection of aluminum structures is partly based on application of a primer containing inhibitors. In such coatings, release of the inhibiting species enables fast healing of a bare metal surface after a mechanical damage of the protective layers. Nevertheless, considering possible depletion of inhibitors by uncontrolled leaching, it appears important to estimate the corrosion risk integrating “corrosion” sensors in the structure. The objective of this work was to understand the operating mode of a sensor simulating a damaged paint coating whose concept is based on the competition between the triggering of localized corrosion and the pas…
Equilibres divariants entre la vapeur d'eau et les hydrates solides : Caractérisation de la nature de la solution solide, limites du domaine de divar…
1972
National audience; Nous avons récemment proposé (1, 2) deux modèles thermodynamiques pour les équilibres divariants entre la vapeur d'eau et les hydrates salins solides. Le premier postule l'existence d'une solution solide d'insertion d'eau dans le sel, le second postule l'existence d'une solution solide de substitution entre deux hydrates du sel. Le but de ce travail est d'établir un nouveau critère permettant de distinguer les deux modèles à partir de l'expérience et de délimiter le domaine divariant dans chacun des deux cas. Nous supposerons, sauf mention contraire, que la solution d'insertion obéit à la loi de Henry par rapport à l'eau et que la solution de substitution est idéale. Nous…
Phases transitions in complexe oxides with perovskite structure : case system (1-x)Na0,5Bi0,5TiO3 - xCaTiO3
2015
The solid solutions (1-x)Na0,5Bi0,5TiO3 (NBT) – xCaTiO3 (CT) were studied by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, impedance spectroscopy and DSC. These materials have a perovskite crystalline structure. This study reveals not only the complexity but also the richness of physical phenomena in these compounds: phases transitions sequences, the Ca2+ effect on the physical-chemistry properties and the relation between dielectric properties and crystalline structure. Thereby, (1-x)NBT – xCT solid solutions (0 ≤ x ≤ 1.00) were synthesized by chemical solid route, then they were sintered by a particular procedure in order to avoid sodium and bismuth volatilization. …