Constitutive modeling of dynamic strain aging in niobium
Modified VA Model, Dynamic Strain Aging, Thermal Activation Energy, Niobiumdownload PDF
Abstract. As the temperature rises, metals should lose strength. However, under some combinations of strain rate and temperature, they show a dramatic increase in strength due to the interaction of impurity/solute atoms with the dislocations, a phenomenon known as dynamic strain aging (DSA). Thermomechanical stress-strain curves have been modeled using a variety of numerical approaches, but accurately modeling DSA activation remains a challenge. The activation free energy for dislocation movement rises during DSA, as there are more solute atoms concentrated at the local barriers. As a result, we see an increase in strength. This work modifies the physical parameters-based VA model for commercially pure bcc Niobium, which is known to display DSA at low strain rates and elevated temperatures, in order to create a constitutive model that can accurately capture DSA.
Modified VA Model, Dynamic Strain Aging, Thermal Activation Energy, Niobium
Published online 8/10/2023, 7 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Modified VA Model, Dynamic Strain Aging, Thermal Activation Energy, Niobium, Constitutive modeling of dynamic strain aging in niobium, Materials Research Proceedings, Vol. 31, pp 128-134, 2023
The article was published as article 14 of the book Advanced Topics in Mechanics of Materials, Structures and Construction
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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