A new invariant-based thermo-plastic model for finite deformation analysis of short fibre reinforced composites: Development and numerical aspects

A novel invariant-based thermo-plastic model for finite deformation analysis of short fibre reinforced composites is presented including aspects of its numerical implementation. The underlying concept complies with thermodynamic restrictions, allowing a robust and consistent modeling framework. The main novelties of the current investigation concern: (i) an alternative definition of the plastic potential function assuming a non-associative plastic formulation, and (ii) the update of the preferential material orientation along the thermo-plastic deformation process using a geometrically nonlinear description. On the computational side, the derivation of an internal variable formulation using an objective integration algorithm and the closed-form of the consistent tangent moduli are outlined. The performance of the proposed model is assessed via a set of numerical simulations, which demonstrate its applicability and robustness.