Experimental Mechanics

, Volume 13, Issue 10, pp 422–432 | Cite as

The effect of strain rate and heat developed during deformation on the stress-strain curve of plastics

Temperature rise developed during deformation can have significant effects on the stress-strain relationship. Four hard plastics are tested at various strain rates, and temperature changes are measured during deformation of the specimen
  • S. C. Chou
  • K. D. Robertson
  • J. H. Rainey
Article

Abstract

Polymethylmethacrylate, cellulose acetate butyrate, polypropylene and nylon 6–6 have been characterized in compression at various strain rates from 10−4 s−1 to 103 s−1 at room temperature. A medium strain-rate machine and a split-Hopkinson-bar apparatus are used in conducting the experiments. The temperature rise developed during deformation is also measured by using a thermocouple. All four materials tested definitely show a viscous effect at the beginning of the deformation and a plastic flow follows thereafter. Test results also indicate that the temperature rise developed during deformation cannot be neglected in determining the dynamic response of those materials investigated in this study.

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Copyright information

© Society for Experimental Mechanics, Inc. 1973

Authors and Affiliations

  • S. C. Chou
    • 1
  • K. D. Robertson
    • 1
  • J. H. Rainey
    • 1
  1. 1.Army Materials and Mechanics Research CenterWaterton

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