A Priori Pulse Shaper Design for Constant-Strain-Rate Tests of Elastic-Brittle Materials

Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)

Abstract

Pulse shaping techniques have been used for many years now in Kolsky bar testing of brittle materials. The use of pulse shapers allow the experimentalist to conduct high-strain-rate tests on brittle materials while ensuring that the sample will achieve a state of dynamic stress equilibrium before it fails, as well as to achieve a constant-strain-rate loading state for a large portion of the test. The process of choosing the appropriate pulse shaper system has typically been one of trail-and-error, sometimes requiring many experimental trails to achieve optimal results. Advances in analytic modeling of Kolsky bar tests now make it possible, in an a priori fashion, to design a pulse shaper system to produce a known constant-strain-rate experiment. This paper describes the approach of coupling these analytic models to an optimization technique to quickly find a pulse shaper system that will produce an experiment at a known constant-strain-rate. Experiments were conducted and the model predictions compared to resulting strain-rate histories for a G-10 material.

Notes

Acknowledgements

This work was partially supported by Sandia National Laboratories. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.

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Copyright information

© The Society for Experimental Mechanics, Inc. 2013

Authors and Affiliations

  1. 1.Mechanical Engineering DepartmentThe University of TexasSan AntonioUSA
  2. 2.Terminal Ballistics Technology DepartmentSandia National LaboratoriesAlbuquerqueUSA

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