Bending behavior of multilayered textile composite prepregs: Experiment and finite element modeling

An accurate model and assessment of out-of-plane bending properties can improve the forming predictions of multilayered textile prepregs using a suitable modeling technique. This paper aims to investigate the bending properties of multilayered textile thermosetting composite prepregs under conditions relevant to the forming process. A finite element model based on a viscoelastic approach has been developed to predict the bending behavior of different stacking sequences at different processing parameters, including temperature and rate. This model allows the modeler to determine the correct bending parameter values to set during the forming simulation process. The effect of stacking sequences on out-of-plane bending deformation was studied experimentally and numerically through the developed modeling methodology. Furthermore, the paper analyzes the feasibility of using a viscoelastic material model to model the bending behavior of rate-dependent material and its application in forming simulation. A comparison between elastic and viscoelastic material models showed the importance of considering the rate dependency to describe the bending behavior of prepreg materials. The experimental and numerical results show that the bending properties strongly depend on the fabric lay-up inside multiple stacked plies. Bending and friction properties were also found to significantly influence the occurrence of wrinldes during the forming simulation. (C) 2017 Elsevier Ltd. All rights reserved.