On the utilization of radial extrusion to characterize fracture forming limits. Part II: testing and modelling

On the utilization of radial extrusion to characterize fracture forming limits. Part II: testing and modelling

Rui F.V. Sampaio, João P.M. Pragana, Ivo M.F. Bragança, Carlos M.A. Silva, Chris V. Nielsen, Paulo A.F. Martins

Abstract. This second part of the paper is focused on double-action radial extrusion testing and modelling to characterize material formability and failure in the bulk-to-sheet material flow transitions that are commonly found in metal forming. Results show that three-dimensional to plane-stress evolutions at the radially extruded flanges lead to different modes of fracture (by tension and by shear) that may or may not be preceded by necking. The use of double-action radial extrusion as a formability test also reveals adequate to characterize the failure limits of very ductile metallic materials, which cannot be easily determined by conventional upset compression tests, and to facilitate the identification of the instant of cracking and of the corresponding fracture strains by combination of the force vs. time evolutions with the in-plane strains obtained from digital image correlation.

Keywords
Forming, Failure, Stress State Transitions

Published online 3/17/2023, 8 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Rui F.V. Sampaio, João P.M. Pragana, Ivo M.F. Bragança, Carlos M.A. Silva, Chris V. Nielsen, Paulo A.F. Martins, On the utilization of radial extrusion to characterize fracture forming limits. Part II: testing and modelling, Materials Research Proceedings, Vol. 25, pp 237-244, 2023

DOI: https://doi.org/10.21741/9781644902417-30

The article was published as article 30 of the book Sheet Metal 2023

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. 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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