Simulation of Viscous Textile Composite Sheet Forming Based on a Unit Cell Energy Model

An explicit commercial Finite Element (FE) code is used to simulate the forming of a thermoplastic viscous textile composite sheet over a hemispherical tool. The main success of this work is in combining two distinct models. The first model is a non-orthogonal rate-independent constitutive model that has been implemented previously in a commercial FE code [1, 2]. The second is a rate and temperature dependent unit cell energy model [3, 4], designed to predict the shear force – shear angle – shear rate response of viscous textile composites. The combined implementation of these two models in the explicit FE code means that, given the fibre volume fraction and matrix rheology of the composite sheet, accurate predictions of the material’s forming behaviour can be performed without the need for extensive material characterisation experiments. Both models are reviewed briefly and the method of combining these models in the code is described. Finally, results of preliminary forming simulations using a hemispherical tool are presented and discussed.