Filling simulation and mechanical property prediction in the injection moulding of discrete long glass fibre reinforced plastics (LGFRP)

Rectangular plates of long glass fibre reinforced polypropylene were injection moulded and specimens were cut from them. Flexural and tensile tests were carried out to experimentally evaluate the distribution of mechanical properties throughout the plate. Despite the simple shape, a complex distribution was observed due to the material flow during filling. The best properties were measured far from the gate in the longitudinal direction and near the plate edges in the transversal direction. A filling simulation was performed by means of commercial SW, by extracting the flow front shape during injection and the final average orientation in the plate. Numerical results are in agreement with experimental observations, allowing a prediction about the distribution of mechanical properties.