The non-proportional loading of mild steel

The non-proportional loading of mild steel

HAZRA Sumit, DHARA Sisir, TAYLOR Scott, FIGIEL Łukasz

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Abstract. The effect of proportional loading on formability has been extensively studied. However, non-proportional loading occurs frequently in a stamping operation and its impact on formability has been studied less. Non-proportional loading occurs in two areas of stamping: continuously during the draw stage of a complex geometry and discontinuously through stamping stages. Studies on non-proportionality (eg. [1]) show that it can change the formability of a material compared to when it is loaded proportionally. This paper introduces an experimental method that allows a comparison of the deformation in mild steel subject to continuous and discontinuous loading mechanisms. A notable innovation of the method is that it can be carried out inside the chamber of a scanning electron microscope, allowing in-situ measurements of plastic deformation. The experiments show that the plastic behavior of the material under the continuous mode is distinct to when it is deformed discontinuously

Strain Path Change, In-Situ Microstructure Evaluations, Formability

Published online 4/24/2024, 6 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: HAZRA Sumit, DHARA Sisir, TAYLOR Scott, FIGIEL Łukasz, The non-proportional loading of mild steel, Materials Research Proceedings, Vol. 41, pp 977-982, 2024


The article was published as article 107 of the book Material Forming

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