Soutenance de Gyu seok KIM

Le 15 avril 2011 à 14h Amphithéatre A010 Batiment ENSE3 Site Ampère Thèse préparée dans le laboratoire SIMaP, sous la direction conjointe de M. Marc FIVEL et Mme.Emilie FERRIE et Mme.ERICA LILLEODDEN. Résumé A combined experimental and computational investigation of the deformation behavior of pure magnesium single crystal at the micron length scale has been carried out. Employing the recently exploited method of microcompression testing, uniaxial microcompression experiments have been performed on magnesium single crystals with [0001], [2-1-12], [10-11], [11-20] and [10-10] compression axes. The advantage of the microcompression method over conventional mechanical testing techniques is the ability to localize a single crystalline volume which is characterizable after deformation. The stress-strain relations resulting from microcompression experiments is presented and discussed in terms of orientation dependent slip activity and twinning mechanisms and an anisotropic size effect. Such a mechanistic picture of the deformation behavior is revealed through SEM, EBSD and TEM characterization of the deformation structures, and further supported by 3D discrete dislocation dynamics simulations. Membres du Jury M. Edgar RAUCH (CNRS) M. Marc LEGROS (CNRS) M. Heung Nam HAN (Seoul National University) M. Daniel WEYGAND (KIT) M. Marc FIVEL (CNRS) Mme. Erica LILLEODDEN (HZG) Mme. Emilie FERRIE (Grenoble INP)