Shear and compression behaviour of sheet moulding compounds

At the present time, the rheology of sheet moulding compounds (SMC) during forming is not well known. In order to provide better experimental data, an experimental program was carried out as a result of the development of a new rheometer especially dedicated to this kind of material. Homogeneous simple compression and simple shear tests are presented. They allow the evaluation of the influence of the main parameters on the SMC behaviour: strain rate, temperature and fibre fraction. It is shown that the SMC can be considered as a strongly anisotropic non-linear viscous medium.