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Title: Modeling of 3D Aluminum Polycrystals during Large Deformations

Abstract

An approach for generating, meshing, and modeling 3D polycrystals, with a focus on aluminum alloys, subjected to large deformation processes is presented. A Potts type model is used to generate statistically representative grain structures with periodicity to allow scale-linking. The grain structures are compared to experimentally observed grain structures to validate that they are representative. A procedure for generating a geometric model from the voxel data is developed allowing for adaptive meshing of the generated grain structure. Material behavior is governed by an appropriate crystal, elasto-viscoplastic constitutive model. The elastic-viscoplastic model is implemented in a three-dimensional, finite deformation, mixed, finite element program. In order to handle the large-scale problems of interest, a parallel implementation is utilized. A multiscale procedure is used to link larger scale models of deformation processes to the polycrystal model, where periodic boundary conditions on the fluctuation field are enforced. Finite-element models, of 3D polycrystal grain structures will be presented along with observations made from these simulations.

Authors:
; ; ;  [1]
  1. Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States)
Publication Date:
OSTI Identifier:
21057395
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 908; Journal Issue: 1; Conference: NUMIFORM '07: 9. international conference on numerical methods in industrial forming processes, Porto (Portugal), 17-21 Jun 2007; Other Information: DOI: 10.1063/1.2740843; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINIUM; ALUMINIUM ALLOYS; BOUNDARY CONDITIONS; COMPUTERIZED SIMULATION; CRYSTAL STRUCTURE; DEFORMATION; ELASTICITY; FINITE ELEMENT METHOD; FLUCTUATIONS; MATHEMATICAL MODELS; MICROSTRUCTURE; PERIODICITY; PLASTICITY; POLYCRYSTALS; SCALE MODELS; THREE-DIMENSIONAL CALCULATIONS

Citation Formats

Maniatty, Antoinette M., Littlewood, David J., Lu Jing, and Pyle, Devin. Modeling of 3D Aluminum Polycrystals during Large Deformations. United States: N. p., 2007. Web. doi:10.1063/1.2740843.
Maniatty, Antoinette M., Littlewood, David J., Lu Jing, & Pyle, Devin. Modeling of 3D Aluminum Polycrystals during Large Deformations. United States. doi:10.1063/1.2740843.
Maniatty, Antoinette M., Littlewood, David J., Lu Jing, and Pyle, Devin. Thu . "Modeling of 3D Aluminum Polycrystals during Large Deformations". United States. doi:10.1063/1.2740843.
@article{osti_21057395,
title = {Modeling of 3D Aluminum Polycrystals during Large Deformations},
author = {Maniatty, Antoinette M. and Littlewood, David J. and Lu Jing and Pyle, Devin},
abstractNote = {An approach for generating, meshing, and modeling 3D polycrystals, with a focus on aluminum alloys, subjected to large deformation processes is presented. A Potts type model is used to generate statistically representative grain structures with periodicity to allow scale-linking. The grain structures are compared to experimentally observed grain structures to validate that they are representative. A procedure for generating a geometric model from the voxel data is developed allowing for adaptive meshing of the generated grain structure. Material behavior is governed by an appropriate crystal, elasto-viscoplastic constitutive model. The elastic-viscoplastic model is implemented in a three-dimensional, finite deformation, mixed, finite element program. In order to handle the large-scale problems of interest, a parallel implementation is utilized. A multiscale procedure is used to link larger scale models of deformation processes to the polycrystal model, where periodic boundary conditions on the fluctuation field are enforced. Finite-element models, of 3D polycrystal grain structures will be presented along with observations made from these simulations.},
doi = {10.1063/1.2740843},
journal = {AIP Conference Proceedings},
number = 1,
volume = 908,
place = {United States},
year = {Thu May 17 00:00:00 EDT 2007},
month = {Thu May 17 00:00:00 EDT 2007}
}
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