Pre-strain correction of forming limit curves

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Pre-strain correction of forming limit curves

ARETZ Holger

Abstract. Inherent features of the Nakajima test to determine forming limit curves (FLC) are inevitable bending strains and pre-strains originating from evolving punch contact in the early stage. Both effects are very annoying and bias the resulting FLC considerably, so that a direct comparison of materials with different gauges is impossible. In the present work, a simple computational procedure is developed to remove both effects from FLC data. Application examples demonstrate its capabilities.

Keywords
Sheet Metal Forming, Forming Limit Curve, Strain-Path Dependence

Published online 4/24/2024, 10 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: ARETZ Holger, Pre-strain correction of forming limit curves, Materials Research Proceedings, Vol. 41, pp 948-957, 2024

DOI: https://doi.org/10.21741/9781644903131-104

The article was published as article 104 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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