Background The multiple loadings in a conventional Kolsky bar test prevent an in-depth understanding of the relationship between microstructure change and load history under dynamic loading. Objective In order to correlate the microstructural changes to the dynamic load history, it is necessary to develop a new dynamic test capability that allows the specimen be incrementally deformed with a singular loading for each strain increment. Methods A dynamic incremental strain and singular strain loading (DI <InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="11340_2025_1159_Article_IEq1.gif" Format="GIF" Height="10" Rendition="HTML" Resolution="72" Type="Linedraw" Width="10" /> </InlineMediaObject> <EquationSource Format="TEX">$\epsilon$</EquationSource> <EquationSource Format="MATHML"><math> <mi>ϵ</mi> </math></EquationSource> </InlineEquation> SϵL) capability based on Kolsky tension bar technique was developed. Different design options and considerations are presented to facilitate the DI <InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="11340_2025_1159_Article_IEq1.gif" Format="GIF" Height="10" Rendition="HTML" Resolution="72" Type="Linedraw" Width="10" /> </InlineMediaObject> <EquationSource Format="TEX">$\epsilon$</EquationSource> <EquationSource Format="MATHML"><math> <mi>ϵ</mi> </math></EquationSource> </InlineEquation> SϵL capability such that the user can choose the combination that best meets their test requirements. Results To demonstrate the new capability, a dog-bone shaped 316L stainless steel was subjected to a series of dynamic tensile loadings with an incremental strain of ~ 11% for each singular loading test. The 316L stainless steel specimens were subjected to a singular loading but different strains under adiabatic condition. At the same dynamic strain rate, the 316L stainless steel became softer and less ductile under adiabatic condition due to adiabatic heating. Conclusions With this new capability, one could decouple the thermosoftening from a conventional dynamic tension test for predictive rate-dependent material model development. The information obtained from this capability may also be used to determine microstructural change and/or damage evolution during dynamic tension testing.

Development of Kolsky Tension Bar Based Dynamic Incremental Strain and Singular Strain Loading Capability

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发表日期：

2025年2月19日

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B. Song,
T. Martinez,
A. Y. Ku,
J. Deitz,
P. Noell

摘要

Background

The multiple loadings in a conventional Kolsky bar test prevent an in-depth understanding of the relationship between microstructure change and load history under dynamic loading.

Objective

In order to correlate the microstructural changes to the dynamic load history, it is necessary to develop a new dynamic test capability that allows the specimen be incrementally deformed with a singular loading for each strain increment.

Methods

A dynamic incremental strain and singular strain loading (DI $\epsilon$ $ϵ$ SϵL) capability based on Kolsky tension bar technique was developed. Different design options and considerations are presented to facilitate the DI $\epsilon$ $ϵ$ SϵL capability such that the user can choose the combination that best meets their test requirements.

Results

To demonstrate the new capability, a dog-bone shaped 316L stainless steel was subjected to a series of dynamic tensile loadings with an incremental strain of ~ 11% for each singular loading test. The 316L stainless steel specimens were subjected to a singular loading but different strains under adiabatic condition. At the same dynamic strain rate, the 316L stainless steel became softer and less ductile under adiabatic condition due to adiabatic heating.

Conclusions

With this new capability, one could decouple the thermosoftening from a conventional dynamic tension test for predictive rate-dependent material model development. The information obtained from this capability may also be used to determine microstructural change and/or damage evolution during dynamic tension testing.