Molecular dynamics simulation for determining dislocation strengthening coefficient in BCC iron

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Molecular dynamics simulation for determining dislocation strengthening coefficient in BCC iron

MIYAZAWA Naoki, HAMA Takayuki

Abstract. Crystal plasticity models are promising numerical analysis methods for predicting and evaluating material forming processes. In crystal plasticity analyses, the dislocation density model, often based on the Bailey-Hirsch equation, is employed to represent the work hardening behavior of metallic materials. The dislocation strengthening coefficient is a proportional factor between the square root of dislocation density with the slip resistance. Therefore, the appropariate determination of the dislocation strengthening coefficient is crucial to perform reliable material forming analyses using crystal plasticity models. Previously, dislocation strengthening coefficients have been determined using dislocation dynamics simulations. However, dislocation dynamics simulations cannot accurately account for elastic anisotropy due to its computational cost. To address this limitation, we conducted molecular dynamics simulations to determine dislocation strengthening coefficient in bcc iron. Molecular dynamics simulations of dislocation-dislocation interaction analysis can be expected to determine the dislocation strengthening coefficient accurately, including the effects of elastic anisotropy of metallic materials.

Keywords
Molecular Dynamics Simulation, Crystal-Plasticity Analysis, Dislocation Strengthening

Published online 4/24/2024, 6 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: MIYAZAWA Naoki, HAMA Takayuki, Molecular dynamics simulation for determining dislocation strengthening coefficient in BCC iron, Materials Research Proceedings, Vol. 41, pp 983-988, 2024

DOI: https://doi.org/10.21741/9781644903131-108

The article was published as article 108 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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