Development of the cross-section moment in air-bending

Development of the cross-section moment in air-bending


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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.

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


The article was published as article 113 of the book Material Forming

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