Simple multiaxial tests to assess dynamic ductility of 17-4PH

Simple multiaxial tests to assess dynamic ductility of 17-4PH

MANCINI Edoardo, CORTIS Gabriele, CORTESE Luca, UTZERI Mattia, SASSO Marco

Abstract. To investigate material ductility, the use of simple multiaxial specimens which can be tested through a common tensile machine or by a Split Hopkinson bar facility would allow avoiding the use of more complex equipment to induce different stress states in the investigated material. In this work, experimental dynamic tests have been performed on four different specimen geometries on a 17-4PH steel by a direct Split Hopkinson Bar (SHB). Finite element models of the experiments are set up and used jointly with experimental data to calibrate and validate a strain rate dependent plasticity model, and to extract the local values of stress and ultimate strain in the most critical point of the samples, at fracture. These latter results allowed the calibration of a ductile damage model, whose predictions, compared with a previous calibration using tests carried out in quasi-static conditions, confirmed the effectiveness of the proposed specimens and test methodology to assess material ductility under dynamic conditions.

Keywords
Ductile Damage Modelling, High Strain Rate, Material Characterization

Published online 4/19/2023, 8 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: MANCINI Edoardo, CORTIS Gabriele, CORTESE Luca, UTZERI Mattia, SASSO Marco, Simple multiaxial tests to assess dynamic ductility of 17-4PH, Materials Research Proceedings, Vol. 28, pp 1379-1386, 2023

DOI: https://doi.org/10.21741/9781644902479-149

The article was published as article 149 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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