Computer Simulation and Analysis of the Expanding Ring Test

  • John E. Reaugh


Explosively launched expanding ring tests have been used to extract material flow stress at strain-rates from 103 to 3 x 104 sec−1. Computer simulations of such tests using a strain-rate independent, but work hardening constitutive model were analyzed by the same methods used experimentally. Results of this analysis also showed an apparent strain-rate effect. Further examination of the computer simulations has shown that much, if not all, of the measured strain-rate effect is an increased flow stress due to a plastic strain, ɛL, that is locked in during the initial stages of launch. At a larger launch velocity, hence a larger strain-rate, ɛL is also larger. The value of ɛL is sensitive to details of the launch dynamics.


Explosive Hemp 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    C. R. Hoggatt and R. F. Recht, “Stress-Strain Data Obtained at High Rates Using an Expanding Ring”, Experimental Mechanics, (9), 441–448, Oct. 1969.CrossRefGoogle Scholar
  2. 2.
    A. E. Carden, P. E. Williams, R. R. Karp, Comparison of the Flow Curves of 6061 Aluminum Alloy at High and Low Strain Rates, in,: Shock Waves and High-Strain-Rate Phenomena in Metals, M. A. Meyers and L. E. Murr, eds., Plenum, 1981, pp. 37–50.Google Scholar
  3. 3.
    M. L. Wilkins, R. D. Streit, J. E. Reaugh, “Cumulative-Strain-Damage Model of Ductile Fracture: Simulation and Prediction of Engineering Fracture Tests”, Lawrence Livermore National Laboratory, Livermore, CA, UCRL-53058 (1980).CrossRefGoogle Scholar
  4. 4.
    M. L. Wilkins, “Calculations of Elastic-Plastic Flow”, in: Methods in Computational Physics, Vol. 3 Fundamental Methods in Hydrodynamics, B. Alder, ed., Academic Press, N. Y., 1964, pp. 211–263.Google Scholar
  5. 5.
    C. J. Maiden and S. J. Green, Compressive Strain Rate Tests on Six Selected Materials at Strain Rates from 10-3 to 104 in./in./sec, J. Appl. Mech., p. 496, Sept. 1966.Google Scholar
  6. 6.
    C. H. Mok and J. Duffy, “The Dynamic Stress-Strain Relation of Metals as Determined from Impact Tests with a Hard Ball”, Brown Univ. Rept. Nonr-562(20) 137, June 1964.Google Scholar
  7. 7.
    A. L. Austin and R. F. Steidel, Jr., A Method for Determining the Tensile Properties of Metals at High Rates of Strain, Proc. SESA. XVII (1), pp. 99–114, 1959.Google Scholar
  8. 8.
    U. S. Lindholm and L. M. Yeakley, High Strain-Rate Testing: Tension and Compression, Experimental Mechanics, 8 (1), pp. 1–9, 1968.CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • John E. Reaugh
    • 1
  1. 1.Physics DepartmentLawrence Livermore National LaboratoryLivermoreUSA

Personalised recommendations