Modelling of short fibre-reinforced thermoplastics' flows in polymer processing

Abstract : Short fibre-reinforced thermoplastics have improved mechanical properties which depend on fibre orientation. Moreover, the flow can be changed by the presence of the fibres. Flow and fibre orientation modelling can help using this kind of materials at best. Fibre orientation laws and constitutive equations for anisotropic suspensions are reviewed. Those that are practically useful in polymer processing situations are still based on important assumptions. Fibre orientation is an additional unknown with respect to classical problems. Numerical models of extrusion and injection moulding can be used to improve die or mould design.