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Title: Development of Multi-Scale Finite Element Analysis Codes for High Formability Sheet Metal Generation

Abstract

In this study, the dynamic- and static-explicit multi-scale finite element (F.E.) codes are developed by employing the homogenization method, the crystalplasticity constitutive equation and SEM-EBSD measurement based polycrystal model. These can predict the crystal morphological change and the hardening evolution at the micro level, and the macroscopic plastic anisotropy evolution. These codes are applied to analyze the asymmetrical rolling process, which is introduced to control the crystal texture of the sheet metal for generating a high formability sheet metal. These codes can predict the yield surface and the sheet formability by analyzing the strain path dependent yield, the simple sheet forming process, such as the limit dome height test and the cylindrical deep drawing problems. It shows that the shear dominant rolling process, such as the asymmetric rolling, generates ''high formability'' textures and eventually the high formability sheet. The texture evolution and the high formability of the newly generated sheet metal experimentally were confirmed by the SEM-EBSD measurement and LDH test. It is concluded that these explicit type crystallographic homogenized multi-scale F.E. code could be a comprehensive tool to predict the plastic induced texture evolution, anisotropy and formability by the rolling process and the limit dome height test analyses.

Authors:
;  [1]; ;  [2];  [3];  [4]
  1. Osaka Institute of Technology, 5-16-1Omiya, Asahiku Osaka, 535-8585 Japan (Japan)
  2. Osaka Sangyo University, 3-1-1 Nakagaito, Daito, Osaka, 574-8530 Japan (Japan)
  3. Kumamoto University, 2-39-1, Kurokami, Kumamoto, 860-8555 (Japan)
  4. The Furukawa Electric Co. Ltd., 2-4-3 Okano, Nishiku, Yokohama, 220-0073 (Japan)
Publication Date:
OSTI Identifier:
21057388
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: 10.1063/1.2740814; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALLOYS; ANISOTROPY; BACKSCATTERING; COMPUTERIZED SIMULATION; DRAWING; ELECTRON DIFFRACTION; FINITE ELEMENT METHOD; HARDENING; METALS; MORPHOLOGICAL CHANGES; MORPHOLOGY; PLASTICITY; POLYCRYSTALS; ROLLING; SCANNING ELECTRON MICROSCOPY; SHEAR; SHEETS; STRAINS; SURFACES; TEXTURE

Citation Formats

Nnakamachi, Eiji, Kuramae, Hiroyuki, Ngoc Tam, Nguyen, Nakamura, Yasunori, Sakamoto, Hidetoshi, and Morimoto, Hideo. Development of Multi-Scale Finite Element Analysis Codes for High Formability Sheet Metal Generation. United States: N. p., 2007. Web. doi:10.1063/1.2740814.
Nnakamachi, Eiji, Kuramae, Hiroyuki, Ngoc Tam, Nguyen, Nakamura, Yasunori, Sakamoto, Hidetoshi, & Morimoto, Hideo. Development of Multi-Scale Finite Element Analysis Codes for High Formability Sheet Metal Generation. United States. doi:10.1063/1.2740814.
Nnakamachi, Eiji, Kuramae, Hiroyuki, Ngoc Tam, Nguyen, Nakamura, Yasunori, Sakamoto, Hidetoshi, and Morimoto, Hideo. Thu . "Development of Multi-Scale Finite Element Analysis Codes for High Formability Sheet Metal Generation". United States. doi:10.1063/1.2740814.
@article{osti_21057388,
title = {Development of Multi-Scale Finite Element Analysis Codes for High Formability Sheet Metal Generation},
author = {Nnakamachi, Eiji and Kuramae, Hiroyuki and Ngoc Tam, Nguyen and Nakamura, Yasunori and Sakamoto, Hidetoshi and Morimoto, Hideo},
abstractNote = {In this study, the dynamic- and static-explicit multi-scale finite element (F.E.) codes are developed by employing the homogenization method, the crystalplasticity constitutive equation and SEM-EBSD measurement based polycrystal model. These can predict the crystal morphological change and the hardening evolution at the micro level, and the macroscopic plastic anisotropy evolution. These codes are applied to analyze the asymmetrical rolling process, which is introduced to control the crystal texture of the sheet metal for generating a high formability sheet metal. These codes can predict the yield surface and the sheet formability by analyzing the strain path dependent yield, the simple sheet forming process, such as the limit dome height test and the cylindrical deep drawing problems. It shows that the shear dominant rolling process, such as the asymmetric rolling, generates ''high formability'' textures and eventually the high formability sheet. The texture evolution and the high formability of the newly generated sheet metal experimentally were confirmed by the SEM-EBSD measurement and LDH test. It is concluded that these explicit type crystallographic homogenized multi-scale F.E. code could be a comprehensive tool to predict the plastic induced texture evolution, anisotropy and formability by the rolling process and the limit dome height test analyses.},
doi = {10.1063/1.2740814},
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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