Deformation heterogeneity and intragrain lattice misorientation in high strength contrast, dual-phase bridgmanite/periclase

[Display omitted] A bridgmanite/periclase aggregate is investigated due to its prevalence in the Earth’s lower mantle and its importance for understanding geodynamic processes. In dual-phase polycrystalline aggregates, both strength contrast between phases and single crystal elastic and plastic anis...

Full description

Saved in:
Bibliographic Details
Published in:Acta materialia 2020-05, Vol.189 (C), p.284-298
Main Authors: Kasemer, Matthew, Zepeda-Alarcon, Eloisa, Carson, Robert, Dawson, Paul, Wenk, Hans-Rudolf
Format: Article
Language:English
Subjects:
Bridgmanite
Crystal plasticity
Finite element method
MATERIALS SCIENCE
Periclase
Strength contrast
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:[Display omitted] A bridgmanite/periclase aggregate is investigated due to its prevalence in the Earth’s lower mantle and its importance for understanding geodynamic processes. In dual-phase polycrystalline aggregates, both strength contrast between phases and single crystal elastic and plastic anisotropy are known to influence the development of intragrain misorientation, and the evolution of crystallographic texture. In this study, full-field crystal plasticity simulations are performed with a finite element solution method, and applied to an aggregate of a mechanically strong orthorhombic phase with perovskite structure (bridgmanite, MgSiO3), and a relatively weaker cubic phase (periclase, MgO). The relative strengths of the phases are parameterized to elucidate the effect that strength contrast has on texture evolution and single-phase simulations are performed for comparison. Overall, results indicate that the relative strength between the two phases influences the development of plasticity, and the overall texture evolution. Results are discussed in light of trends related to the evolution of plasticity and misorientation in the aggregate, and their dependence on both the strength contrast between phases as well as the spatial distribution of grains and phases.
ISSN:1359-6454
1873-2453
DOI:10.1016/j.actamat.2020.02.061