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Experimental Mechanics

, 45:186 | Cite as

Pulse shaping techniques for testing elastic-plastic materials with a split Hopkinson pressure bar

  • D. J. Frew
  • M. J. Forrestal
  • W. Chen
Article

Abstract

We present pulse shaping techniques to obtain compressive stress-strain data for elastic-plastic materials with a split Hopkinson pressure bar. The conventional split Hopkinson pressure bar apparatus is modified by placing a combination of copper and steel pulse shapers on the impact surface of the incident bar. After impact by the striker bar, the copper-steel pulse shaper deforms plastically and spreads the pulse in the incident bar so that the sample is nearly in dynamic stress equilibrium and has a nearly constant strain rate in the plastic response region. We present analytical models and data that show a broad range of incident strain pulses can be obtained by varying the pulse shaper geometry and striking velocity. For an application, we present compressive stress-strain data for 4340 Rc 43 steel.

Key Words

Hopkinson pressure bar pulse shaping elastic-plastic materials 

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Copyright information

© Society for Experimental Mechanics 2005

Authors and Affiliations

  • D. J. Frew
    • 1
  • M. J. Forrestal
    • 1
  • W. Chen
    • 2
  1. 1.Sandia National LaboratoriesAlbuquerqueUSA
  2. 2.School of Aeronautics and Astronautics and School of Materials EngineeringPurdue UniversityWest LafayetteUSA

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