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Elastic Deformation of Polycrystals

Rajeev Ahluwalia·Turab Lookman·Avadh Saxena
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Abstract

We propose a framework to model elastic properties of polycrystals by coupling crystal orientational degrees of freedom with elastic strains. Our model encodes crystal symmetries and takes into account explicitly the strain compatibility induced long-range interaction between grains. The coupling of crystal orientation and elastic interactions allows for the rotation of individual grains by an external load. We apply the model to simulate uniaxial tensile loading of a 2D polycrystal within linear elasticity and a system with elastic anharmonicities that describe structural phase transformations. We investigate the constitutive response of the polycrystal and compare it to that of single crystals with crystallographic orientations that form the polycrystal.

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Rajeev Ahluwalia, Turab Lookman, Avadh Saxena. 2002-09-18. Elastic Deformation of Polycrystals. https://doi.org/10.1103/physrevlett.91.055501

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