Thesis: Grain-Boundary based deformation mechanisms in ultra-fine grain metals.

This thesis, essentially experimental, consists in deforming several small-grain fcc metals (Cu, Ni, Al) in situ in a dedicated and unique in the world AFM / STM (PPrime Institute, Poiters) and in transmission electron microscopy (TEM)) (CEMES-CNRS, Toulouse). TEM is one of the few techniques capable of imaging grain boundaries in the thickness of the metal (thin slice of a few hundred nm) with nanoscale precision. In situ AFM / STM will complement these observations by revealing, at the atomic scale, the displacements perpendicular to the surface. The combination of the two experiments will provide complete information on the mechanism of shear/migration of grain boundaries under stress. Crystal orientation mappings (TEM or SEM) should be used to characterize the type of migration depending on the type of grain boundary.

This thesis, funded as part of the RODIN project (Role of disconnections in grain boundary-based plasticity – French ANR Agency) can begin between March 2018 and October 2019. The schedule of experiments between Poitiers and Toulouse is flexible, but should be on the order of 50-50 of the 3 years contract. The applicant will have a solid background in materials science and crystallography. Applications should be sent to christophe.coupeau@univ-poitiers.fr and/or marc.legros@cemes.fr 

 For futher information on the subject, see document attached below: