Eulerian finite element implementations of a dislocation density-based continuum model

Journal Article · 30 November 2023 · International Journal of Solids and Structures

DOI: https://doi.org/10.1016/j.ijsolstr.2023.112590 · OSTI ID:2229699

Zecevic, Milovan  ^[1]; Cawkwell, M. J.  ^[1]; Luscher, D. J.  ^[1]

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1. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

In Eulerian finite element simulations, the mesh moves relative to the material. After every change of position between the mesh and the material, the state variables are interpolated to the new mesh position, which is referred to as advection. Large strain crystal plasticity models are based on the multiplicative decomposition of the total deformation gradient. Further, the stress is evaluated as a function of the thermoelastic strain, temperature, and other state variables. Advection of tensor quantities, such as the strain, is coupled with possibly significant advection errors. In an effort to reduce the advection errors, we develop two rate forms of an established dislocation density-based continuum model. To that end, we replace the multiplicative decomposition of the deformation gradient with the additive decomposition of the velocity gradient, and define the stress rate instead of the total stress. The Eulerian implementation is compared with Lagrangian calculations, and two numerical examples with severe deformation levels are presented.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 2229699
• Alternate ID(s): OSTI ID: 2368934
• Report Number(s): LA-UR--23-25027
• Journal Information: International Journal of Solids and Structures, Journal Name: International Journal of Solids and Structures Vol. 288; ISSN 0020-7683
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English