The Influence of Hardening Curve on the Shape and Size of the Neck of Specimen in Tensile Test

Abstract:

The article is devoted to the testing of samples for tensile, namely the formation of the neck. The objective of the study is to establish the qualitative level of influence of the nature of the hardening curve of the material on the shape and size of the neck. By using computer simulation, testing of samples of the two test materials, selected so as to provide the possibility of direct comparisons, forming the necks of the same diameter in the minimum section and the section near the neck, is worked over. It is found that the nature of the hardening curve determines the shape and size of the neck, including the radius of its curvature. This makes it possible to recover the hardening curve for large values of the strain. At the same time, it is established that the equation of the forming neck is invariant to the nature of the hardening curve of the material.

• Periodical: Materials Science Forum (Volume 989)
• Pages: 372-377
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.989.372
• Online since: May 2020
• Authors: Mikhail Erpalov*, Danis Sh. Nukhov
• Keywords: FEM, Flow Stress, Hardening Curve, Neck Formation, Strain, Tensile Test

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