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Published on: April 25, 2019
Theoretical nonlinear response of complex single crystal under multi-axial tensile loading
1Civil, Environmental and Architectural Engineering Department, University of Kansas, 1530 W. 15th Street, Lawrence, KS 66045-7609, USA. amisra@ku.edu
Scientific Reports
|March 20, 2013
Summary
This study explores single crystal mechanical properties using ab initio methods. Hydroxyapatite (HAP) crystals exhibit complex, nonlinear behavior influenced by local structural changes.
Area of Science:
- Materials Science
- Solid Mechanics
- Computational Physics
Background:
- Single crystals are fundamental building blocks whose mechanical properties are crucial.
- Understanding behavior beyond linear elasticity is essential for advanced material applications.
Purpose of the Study:
- To develop and apply a computational approach for analyzing single crystal mechanical properties beyond linear elasticity.
- To investigate the mechanical behavior and anisotropy of stoichiometric hydroxyapatite (HAP) crystals.
Main Methods:
- Utilized density functional theory (DFT) based ab initio calculations.
- Employed large supercells subjected to multi-axial tensile loading.
- Introduced a failure envelope index for material strength quantification.
Main Results:
- Revealed complex, nonlinear, and loading-path dependent mechanical behavior in HAP crystals.
- Observed evolving anisotropy under tensile loading.
- Identified local structural changes as the origin of complex behavior in multi-component crystals.
Conclusions:
- The ab initio approach effectively captures complex single crystal mechanical responses.
- HAP crystals exhibit intricate mechanical properties driven by localized structural dynamics.
- The failure envelope index provides a valuable metric for comparative material strength analysis.
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