Fortran User Subroutine (UMAT) for Abaqus.

This dataset contains the Fortran code for the user subroutine (UMAT) used in the article "A thermo-elasto-viscoplastic model for polymers" (doi.org/10.1016/j.jmps.2018.11.018) by Joakim Johnsen, Arild Holm Clausen, Frode Grytten, Ahmed Benallal and Odd Sture Hopperstad. The dataset also includes an example input file for a thermomechanical axisymmetric uniaxial tensile test built for Abaqus 6.14-4. Note that you need to link Abaqus to a Fortran compiler in order to run the model with the user subroutine.

The following properties must be given in the material card: -- PART A PROPERTIES PROPS(1) : Initial shear modulus Part A PROPS(2) : Temperature sensitivity of shear modulus in Part A PROPS(3) : Activation enthalpy for alpha relaxation PROPS(4) : Activation volume for alpha relaxation PROPS(5) : Reference plastic strain rate for alpha relaxation (give as natural logarithm value) PROPS(6) : Parameter governing evolution of reference plastic strain rate for alpha relaxation PROPS(7) : Activation enthalpy for beta relaxation PROPS(8) : Activation volume for beta relaxation PROPS(9) : Reference plastic strain rate for beta relaxation (give as natural logarithm value) PROPS(10) : Parameter governing evolution of reference plastic strain rate for beta relaxation PROPS(11) : Boltzmann's constant PROPS(12) : Universal gas constant PROPS(13) : Reference temperature PROPS(14) : Tolerance used in convergence criterion PROPS(15) : Maximum number of iterations in the semi-implicit integration -- PART B PROPERTIES PROPS(16) : Initial shear modulus Part B PROPS(17) : Bulk modulus PROPS(18) : Locking stretch PROPS(19) : Thermal expansion coefficient --- COMMON PROPERTIES PROPS(20) : Density PROPS(21) : Specific heat capacity PROPS(22) : Factor controlling substepping