Hexagonal close-packing structure on a cubic cell (original) (raw)
2005, The Journal of chemical physics
AI-generated Abstract
The study presents an algorithm designed to facilitate the construction of hexagonal close-packed (hcp) structures within cubic simulation boxes, addressing the limitations faced in simulations due to the preference for face-centered cubic (fcc) configurations. By utilizing straightforward modifications to the arrangement of atoms in specific layers, the proposed method enables efficient stability testing of various close-packed crystal structures. Additionally, while the algorithm offers a rapid approach for preliminary assessments, it emphasizes the importance of considering small deviations from ideal hcp configurations for more accurate phase comparisons.
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ATOMIC STRUCTURE OF AN fcc-HEXAGONAL INTERFACE
Le Journal de Physique Colloques, 1990
-L'interface entre une matrice cubique à faces centrées et des précipités hexagonaux a été étudiée dans un superalliage par microscopie en faisceau faible et par haute résolution. L'alliage contenant une proportion importante de cobalt, la structure de la seconde phase est hexagonale ordonnée. Les précipités ont une forme de plaquettes parallèles aux plans compacts de la matrice. L' interface est elle même située dans ces plans. Le misfit entre les 2 phases est de 2 %. 3 familles de dislocations coins de vecteurs de Burgers 1/6<112> sont présentes. Ce réseau est triangulaire et possède la particularité de présenter des noeuds à 6 segments de dislocations. Les clichés de microscopie à haute résolution montrent que chaque dislocation est associée à une marche haute de 2 plans atomiques 111. Un modèle géométrique simple identique à celui d'un joint de torsion a été élaboré et rend compte de la géométrie observée.
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