Development of a Material Constitutive for High-Rate Using a Combined Experiment/Computation Method
To describe the high-rate behaviour of metals, a revised form of the classic Johnson-Cook strength model with unknown material constants has been used. The 1D stress-strain relations as well as the effects of strain, strain rate and temperature are examined by Split Hopkinson Pressure Bar (SHPB) test. The undetermined material constants are solved using a variable-dissociation method. The element failure criterion based on maximum equivalent strain is also introduced to estimate the material failure behavior under high strain rate. A corresponding user-defined material subroutine (UMAT) has been developed for revised Johnson-Cook model, which is implemented into ABAQUS. Using this implicit scheme, several groups of finite element simulations under different strain rates are completed in ABAQUS/Standard. The results agree well with the test data and other results by explicit code.
Kikuo Kishimoto, Masanori Kikuchi, Tetsuo Shoji and Masumi Saka
J.F. Lu et al., "Development of a Material Constitutive for High-Rate Using a Combined Experiment/Computation Method", Key Engineering Materials, Vols. 261-263, pp. 269-276, 2004