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A comprehensive plasticity and fracture model was built for metal sheets with application to metal sheet forming and vehicle crash simulations. The combined Bai-Wierzbicki (BW [1]) and CPB06ex2 [2] (or Yld2000-2D [3]) anisotropic plasticity model was further extended to consider elevated temperature effects in additional to the effect of multiaxial stress states. A fully modularized framework was established to combine isotropic, kinematic, and cross hardening behaviors under non-linear loading conditions. The all strain based modified Mohr-Coulomb (eMMC) fracture model was used to consider material anisotropy and nonlinear strain path. The model has been implemented into Abaqus/Explicit as a user material subroutine (VUMAT). Test results on advanced high strength steels, aluminum alloy sheets and magnesium alloy sheets are used to validate the modeling and testing methodologies. Very good correlation was observed between experimental and simulation results.

A fully modularized framework was established to combine isotropic, kinematic, and cross hardening behaviors under non-monotonic loading conditions for advanced high strength steels. Experiments under the following types of non-proportional loading conditions were conducted, 1) uniaxial tension-compression-tension/compression-tension-compression full cycle reversal loading, 2) uniaxial reversal loading with multiple cycles, and 3) reversal shear. The calibrated new model is decoupled between isotropic and kinematic hardening behaviors, and independent on both anisotropic yield criterion and fracture model. Nine materials were calibrated using the model, include: DP590, DP600, DP780, TRIP780, DP980LY, QP980, AK Steel DP980, TBF1180, and AK Steel DP1180. Good correlation was observed between experimental and modeled results.