| Titre : |
Interaction dislocation – joints de grains dans l’Alumine Alpha. |
| Type de document : |
texte imprimé |
| Auteurs : |
Sherazed Moulahem, Auteur ; Omar Khalfallah, Directeur de thèse |
| Editeur : |
جامعة الإخوة منتوري قسنطينة |
| Année de publication : |
2019 |
| Importance : |
222 f. |
| Format : |
30 cm. |
| Note générale : |
2 copies imprimées disponibles
|
| Langues : |
Français (fre) |
| Catégories : |
Français - Anglais
Physique
|
| Tags : |
sciences des matériaux : métallurgie Alumine Alpha Bicristaux Force image Déformation Dislocation Joint de grains Mécanismes d’accommodation Microscopie électronique en
transmission Alumina-Alpha Bicristals Image Force Deformation Grain Boundaries Dislocations Accommodation Mechanisms Transmission Electron Microscopy دود حبيبات المادة انخلا عات قوة الصورة المجهر الالكتروني النافد أكسيد
ألمنيوم الفا ثنائيات تشويه الإنخلاعات ميكانيزمات التكييف |
| Index. décimale : |
530 Physique |
| Résumé : |
The interaction between matrix dislocations and grain boundaries is at the origin of many mechanical properties of polycrystals. Two types of stress transfer processes may occur: slip transmission and matrix dislocation accommodation in boundaries with diffusion. The accommodation mechanisms depend on intergranular structure and dopants. Our investigations done on the alumina-alpha bicrystals, which are in: the rhombohedral twin orientation and Y or Mg doped, and the twin orientation with (011 ̅5) boundary plane and La doped or undoped. The purpose of this study is to calculate the image force due to dislocationgrain boundary interaction and to determine the accommodation process of matrix dislocation during a creep, the deformation conditions (Temperature, Stress, Orientations,) are determined so as to activate two basal slip systems in each grain. * The elastic interaction energy between dislocation and grain boundary is calculated on the basis of the theory of the elasticity in anisotropic materials, and the image force is deduced. The interaction energies determined are represented by the draw iso-energy maps, the maps present no symmetry , the maximal extreme values of the image force is noted for Burgers vector |
| Diplôme : |
Doctorat en sciences |
| En ligne : |
../theses/physique/MOU7486.pdf |
| Format de la ressource électronique : |
pdf |
| Permalink : |
index.php?lvl=notice_display&id=11318 |
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Interaction dislocation – joints de grains dans l’Alumine Alpha.
