A parameter-free strain estimation method to prevent occurrence of splits in sheet forming of complex CAD designs

A parameter-free strain estimation method to prevent occurrence of splits in sheet forming of complex CAD designs


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Abstract. Early detection of manufacturability issues in the design stage is key to avoid long lead times in product development. For various sheet forming processes a critical issue is the occurrence of splits, due to forming beyond the intrinsic formability properties represented by the Forming Limit Curve (FLC). Nevertheless, within industrial engineering practice a detailed manufacturing process simulation including forming limit prediction is not obvious. While commercial Finite Element analysis tools for sheet metal forming are readily available on the market, because of current limitations in availability of accurate data, companies may be rather inclined to choose experimental verification over process simulation analysis. For formability analysis, the required accurate data comprises both material data (hardening data, plastic anisotropy data, FLC data) as well as process data (e.g. non-linear friction data in lubricated system; static or dynamic tool elasticity properties).Therefore, we propose a first-order approximation of the forming deformation, without any parameter (e.g. for material, friction), based solely on conformal flattening of the CAD sheet surface. In this work, we show the usefulness of this method in hydroforming of complex-shaped, industrial parts (bipolar plates). It is shown that from the strain estimation, we can identify the most critically strained regions for individual categories of strain, as formability is known to be greatly dependent on strain mode. The tooling assists to compare design alternatives in terms of formability in the absence of FLC or even basic material data.

Strain Estimate, Conformal Projection, Hydroforming

Published online 4/24/2024, 7 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: EYCKENS Philip, SALAETS Rob, NELISSEN Gert, A parameter-free strain estimation method to prevent occurrence of splits in sheet forming of complex CAD designs, Materials Research Proceedings, Vol. 41, pp 1240-1246, 2024

DOI: https://doi.org/10.21741/9781644903131-138

The article was published as article 138 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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