Temperature dependent tensile and flexural rigidities of a cross-ply thermoplastic for a forming model

Abstract

This paper discusses the characterization of temperature dependent tensile and flexural rigidities for Dyneema® HB80, a cross-ply thermoplastic lamina. The low coefficient of friction of this material posed a challenge to securing specimens during tensile testing. Therefore, modification to the standard gripping method was implemented to facilitate the collection of meaningful test data. Furthermore, a long gauge length was selected to mitigate the influence of slippage on the measure of the elastic modulus. An experimental setup is presented to characterize the bending behavior above ambient temperature conditions based on the vertical cantilever method. The material properties derived from the test data were implemented in a finite element model of the cross ply lamina. The finite element model was generated using a hybrid discrete mesoscopic approach, and deep draw forming of the material was simulated to investigate its formability. Simulation results were compared with an experimental forming trial to demonstrate the capabilities of the model to predict the development of out-of-plane waves during preform manufacturing.