For the modeling of crash-relevant phenomena of unreinforced polymers a temperature- and rate-dependent material model with a hypo-elastic formulation has been implemented on the basis of the modular material model (MMM) of Volkswagen Group Research. The model accounts for the representation of the deformation, the damage and the fracture behavior for crash simulation, built on a profound material characterization. The identification of model parameters is done with a semi-automatic procedure for the three main temperature supporting points -35°C, 20°C and 90°C with the following experiments: uniaxial tension and compression, biaxial tension and shear. The model is implemented to the explicit crash-code Virtual Performance System (VPS) via a user-subroutine. For the calibration of the temperature-dependency, a non-linear interpolation method is proposed, which is based on additional tensile tests at ambient temperatures between the aforementioned supporting points. The additional tensile tests provide information for the variation of the following mechanical properties with temperature: elastic modulus, strain hardening, non-linear plastic Poisson's ratio and fracture strain under uniaxial tension. The model validation is performed with biaxial tensile tests, as well as with component tests of a glove box flap under stress states and temperatures which were not used for model calibration. The modeling with fine discretized volume elements shows a good to very good prediction of the experimental results, while the modeling with more coarse discretized shell elements provides only a first estimation of the fracture behavior.
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