Application of electron tomography of dislocations in beam-sensitive quartz to the determination of strain components

Alexandre Mussi (1) , Julien Gallet (1) , Olivier Castelnau (2) , Patrick Cordier (1)

1 UMET - Unité Matériaux et Transformations - UMR 8207
2 PIMM - Laboratoire Procédés et Ingénierie en Mécanique et Matériaux

In this study we apply electron tomography of dislocations to quartz with a view to assess whether the von Mises-Taylor criterion is satisfied or violated in a deformed crystal of quartz. We propose a method to perform electron tomography with few projected images which allows extension of this technique to beam-sensitive materials such as quartz. The 3D characterization of the dislocation microstructure allows the evaluation of contributions to dislocation mobility with no ambiguity. From the geometrical characteristics of the dislocations and their Burgers vectors, we show how to identify the non-zero components of the strain tensor. We show that in the quartz grain investigated, the von-Mises-Taylor criterion is satisfied thanks to the climb of〈c + a〉dislocations.

Mots clés: TEM; Plasticity; Dislocation; Tomography; Electron-beam sensitive material; Quartz; Climb; von Mises criterion

Domaines: Mécanique des matériaux [physics.class-ph]; Géophysique [physics.geo-ph]

Alexandre Mussi, Julien Gallet, Olivier Castelnau, Patrick Cordier. Application of electron tomography of dislocations in beam-sensitive quartz to the determination of strain components. Tectonophysics, 2021, 803, pp.228754. ⟨10.1016/j.tecto.2021.228754⟩. ⟨hal-03160830⟩