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NASA NTRS · 20205011422

Geometric Requirements for Modeling Polycrystalline Representative Volume Elements Using the Generalized Method of Cells

Abstract

To accurately predict the mechanical response of advanced metallic parts, the grain structure of the metal must be considered and coupled to the macroscale in a multiscale model. The size of the microscale representative volume element must be sufficiently large, and the grid used to discretize the microscale must be adequately refined, in order to ensure an accurate and converged solution. The generalized method of cells is used to predict the mechanical properties of polycrystalline representative volume elements of copper containing randomly oriented grains with the properties of a single face-centered-cubic crystal. Moreover, the results of a parametric study are used to conclude the geometric requirements for an objective microscale model, with respect to the elastic stiffness.

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Evan J Pineda, Luis F Silva, Peter A Gustafson. Geometric Requirements for Modeling Polycrystalline Representative Volume Elements Using the Generalized Method of Cells. https://ntrs.nasa.gov/citations/20205011422

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