Their shorter cycles and processability through thermoforming or overmoulding makes continuous fibre-reinforced thermoplastics an ideal material for the serial production of highly resilient parts, including those used in the automotive segment. Germany’s Fraunhofer Institute for Structural Durability and System Reliability (LBF, Darmstadt; www.lbf.fraunhofer.de) recently developed a new injection moulding process that circumvents the disadvantages associated with this process, including those that arise in thick-walled fibre matrix semi-finished products as well as the quality problems in the bonding of plastic ribbing during the overmoulding stage.

The improved injection moulding process employs extremely thin-walled and thus competitively priced semi-finished products that receive an additional continuous fibre reinforcement in parts that are exposed to extreme stress, including on their edges. The core – which is under much less strain – is filled with a thermoplastic melt that at the same time forms additional ribbing on the surface of the sandwich component. This ribbing emanates from the core through the top coating without creating a joint.