Development of the cross-section moment in air-bending

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Development of the cross-section moment in air-bending

POKKA Aki-Petteri, KESTI Vili, TROIVE Lars, KAIJALAINEN Antti

Abstract. The engineering potential of air-bending as a sheet-metal forming process has been limited by certain challenges related to high-strength steels, strain localization, surface defects, “multi-breakage” and bend shape. The phenomena related to these challenges are not yet fully understood, as the conventional test methods have not provided sufficient data for in-depth analysis of the material behavior in air-bending. In this study, nine thermomechanically rolled steel grades are bent in an air-bending test setup using three different punch radii, and Digital Image Correlation for strain measurement on the outer surface. The development of the cross-section moment is measured from the force-displacement curve. A connection is found between the developments of the cross-section moment, strain distribution and multi-breakage, as well as the strain-hardening properties of the material. The presented results illustrate the potential for predicting bending behavior based on the force-displacement curve, that could be achieved with better understanding of the physics related to the air-bending process.

Keywords
Air Bending, Steel, DIC, Strain Distribution, Bending Moment

Published online 4/24/2024, 11 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: POKKA Aki-Petteri, KESTI Vili, TROIVE Lars, KAIJALAINEN Antti, Development of the cross-section moment in air-bending, Materials Research Proceedings, Vol. 41, pp 1027-1037, 2024

DOI: https://doi.org/10.21741/9781644903131-113

The article was published as article 113 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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