Evaluation of stress-strain curve estimates in dynamic experiments
2010 (English)In: International Journal of Impact Engineering, ISSN 0734-743X, E-ISSN 1879-3509, Vol. 37, no 2, 161-169 p.Article in journal (Refereed) Published
Accurate measurements of the forces and velocities at the boundaries of a dynamically loaded specimen may be obtained using split Hopkinson pressure bars (SHPB) or other experimental devices. However, the determination of a representative stress-strain curve based on these measurements can be challenging. Due to transient effects, the stress and strain fields are not uniform within the specimen. Several formulas have been proposed in the past to estimate the stress-strain curve from dynamic experiments. Here, we make use of the theoretical solution for the waves in an elastic specimen to evaluate the accuracy of these estimates. it is found that it is important to avoid an artificial time shift in the processing of the experimental data. Moreover, it is concluded that the combination of the output force based stress estimate and the average strain provides the best of the commonly used stress-strain curve estimates in standard SHPB experiments.
Place, publisher, year, edition, pages
2010. Vol. 37, no 2, 161-169 p.
Split Hopkinson pressure bar, Dynamic material testing, Stress-strain curve estimate, Evaluation
Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-127370DOI: 10.1016/j.ijimpeng.2009.09.007ISI: 000272856700005OAI: oai:DiVA.org:uu-127370DiVA: diva2:329700