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.
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Frew, D.J., Forrestal, M.J. & Chen, W. Pulse shaping techniques for testing elastic-plastic materials with a split Hopkinson pressure bar. Experimental Mechanics 45, 186–195 (2005). https://doi.org/10.1007/BF02428192
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DOI: https://doi.org/10.1007/BF02428192