Thermo-Kinetic Characterization and Modelling of a New Generation of SMC Composites

Sheet Moulding Compound (SMC) materials are already extensively used in the automotive industry to manufacture semi-structural parts. In order to design and produce structural parts, the development of new SMC formulations with higher reactivity and/or containing high fibre contents is ongoing. To succeed in the optimization of the compression moulding process, it is essential to understand and to model the material behaviour and its properties. In this context, the aim of this study is to develop a thermo-kinetic model in order to be able to describe temperature fields during the compression moulding. This work is firstly focused on the characterization of thermo-physical properties according to the temperature and the degree of cure. The curing behavior is investigated in terms of the modelling kinetic reaction and the evaluation of the associated chemical shrinkage. The thermo-kinetic model is then numerically implemented by taking into account the coupling between thermal gradients and volume changes. A validation of our modelling is performed by making a comparison between results numerically calculated and those experimentally recorded thanks to the PVT-alpha device.