Campus Units
Aerospace Engineering, Mechanical Engineering, Ames Laboratory
Document Type
Article
Publication Version
Submitted Manuscript
Publication Date
2020
Journal or Book Title
arXiv
Abstract
Materials under complex loading develop large strains and often transition via an elastic instability, as observed in both simple and complex systems. Here, we present Si I under large strain in terms of Lagrangian strain by an 5th-order elastic potential found by minimizing error relative to density functional theory (DFT) results. The Cauchy stress-Lagrangian strain curves for arbitrary complex loadings are in excellent correspondence with DFT results, including elastic instability driving Si I→II phase transformation (PT) and the shear instabilities. PT conditions for Si I→II under action of cubic axial stresses are linear in Cauchy stresses in agreement with DFT predictions. Such elastic potential permits study of elastic instabilities and orientational dependence leading to different PTs, slip, twinning, or fracture, providing a fundamental basis for continuum simulations of crystal behavior under extreme loading.
Copyright Owner
The Authors
Copyright Date
2020
Language
en
File Format
application/pdf
Recommended Citation
Chen, Hao; Zarkevich, Nikolai A.; Levitas, Valery I.; Johnson, Duane D.; and Zhang, Xiancheng, "Fifth-degree elastic potential for predictive stress-strain relations and elastic instabilities under large strain and complex loading in Si" (2020). Aerospace Engineering Publications. 161.
https://lib.dr.iastate.edu/aere_pubs/161
Included in
Condensed Matter Physics Commons, Structural Materials Commons, Structures and Materials Commons
Comments
This is a pre-print of the article Chen, Hao, Nikolai A. Zarkevich, Valery I. Levitas, Duane D. Johson, and Xiancheng Zhang. "Fifth-degree elastic potential for predictive stress-strain relations and elastic instabilities under large strain and complex loading in Si." arXiv preprint arXiv:2002.06020 (2020). Posted with permission.