Self-consistent approach for modeling coupled elastic and visco-plastic processes induced by dislocation and pressure solution

Self-consistent approach for modeling coupled elastic and visco-plastic processes induced by dislocation and pressure solution Tingting Xu a , Chlo´ e Arson a,* a Georgia Institute of Technology, School of Civil and Environmental Engineering Abstract This paper pesents a self-consistent approach in which coupled non-linear time-dependent deformation mechanisms are estimated by an aﬃne approximation and elastic and visco-plastic macroscopic properties are calculated for the most general form of anisotropy. Phase changes from crystal to pore are accounted for, via a grain breakage mechanism. As an example, we study dislocation and pressure solution, two non-linear deformation mechanisms com- mon to a wide range of polycrystalline materials. To this date, the couplings between the two are not fully understood. We analyze the sensitivity of the behavior of halite polycrystals to stress, brine content, grain size and grain breakage. Results indicate that: Pressure solution yields mechanical healing only if grain breakage is ignored; Otherwise, pressure solution accelerates dislocation creep, which results in an abrupt increase of elastic and viscoplastic compliance components; Higher stress and/or higher brine content enhance the coupled eﬀects of pressure solution and dislocation; Pressure solution is * Corresponding author Email address: [email protected] (Chlo´ e Arson) Preprint submitted to International Journal of Solids and Structures November 21, 2021

Self-consistent approach for modeling coupled elastic and visco-plastic processes induced by dislocation and pressure solution

Documents

selfconsistent method

elastoviscoplasticity

coupled mechanisms

affine approximation

dislocation

pressure solution

anisotropy