Full field investigation of salt deformation at room temperature: cooperation of crystal plasticity and grain sliding

Mathieu Bourcier (1) , Alexandre Dimanov (1) , Eva Héripré (1) , Jean Raphanel (1) , Michel Bornert (2) , Guillaume Desbois (3)

1 LMS - Laboratoire de mécanique des solides
2 multi-échelle - Modélisation et expérimentation multi-échelle pour les solides hétérogènes
3 RWTH - Rheinisch-Westfälische Technische Hochschule Aachen University

We observed with optical and scanning electron microscopy halite samples during uniaxial compression. Surface displacement fields were retrieved from digital images taken at different loading stages thanks to digital image correlation (DIC) techniques, on the basis of which we could 1) compute global and local strain fields, 2) identify two co-operational deformation mechanisms. The latter were 1) crystal slip plasticity (CSP), as evidenced by the occurrence of slip lines and computed discrete intracrystalline slip bands at the grain surfaces, 2) interfacial micro-cracking and grain boundary sliding (GBS), as evidenced by the computed relative interfacial displacements. The heterogeneities of the strain fields at the aggregate and at the grain scale, and the local contributions of each mechanism were clearly related to the microstructure, i.e. the relative crystallographic orientations of neighboring grains and the interfacial orientations with respect to the principal stress.

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

Mathieu Bourcier, Alexandre Dimanov, Eva Héripré, Jean Raphanel, Michel Bornert, et al.. Full field investigation of salt deformation at room temperature: cooperation of crystal plasticity and grain sliding. Mechanical Behavior of Salt VII, 2012, France. ⟨hal-00866836⟩