Combined material model to predict flow curves of cold forging raw materials having high strain hardening exponent

Combined material model to predict flow curves of cold forging raw materials having high strain hardening exponent

ZEREN Doğuş, KOCATÜRK Fatih, TOPARLI M. Burak

Abstract. In order to increase the accuracy of cold forging simulations, flow curves obtained by experimental compression tests are used instead of the material models existing in the software library. The parameters of Ludwik material model were determined with respect to the constructed experimental flow curves at different temperatures and strain rates. Then, the flow curves were defined into the software by using these parameters. While Ludwik model can represent the material flow curve with high accuracy at low plastic strain values, the error rate between the experimental flow curve and the Ludwik model increases at high plastic strain values. Voce material models were known to predict the flow curve of materials with high strain hardening exponents more accurately, especially at high temperature and strain values. In this study, the performance of Ludwik material model was compared to four Voce material models given in the literature and a more accurate combined material model was defined for each flow curve at different temperature and strain rates for 42CrMoS4 material. All experimental flow curves were predicted with a minimum R2 of 0.99 and the lowest mean absolute error value with the new combined material model.

Keywords
Metal Forming, Voce Material Model, Flow Curve Prediction, Finite Element Method

Published online 4/19/2023, 8 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: ZEREN Doğuş, KOCATÜRK Fatih, TOPARLI M. Burak, Combined material model to predict flow curves of cold forging raw materials having high strain hardening exponent, Materials Research Proceedings, Vol. 28, pp 1503-1510, 2023

DOI: https://doi.org/10.21741/9781644902479-162

The article was published as article 162 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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