Composite panels compete on price on top-end cars

. UK company Advanced Composites Group (ACG) has developed a two-ply system called Zpreg that has already proved itself within the Volkswagen Group – though admittedly it was on a Lamborghini. However, ACG says its technology is cost-effective for production runs of up to 25,000 parts per year, putting it within reach of mainstream carmakers producing top-end niche products. The first ply, using ACG’s partial impregnation technology, comprises a structural fabric coupled to a surface scrim by a high performance resin system. The second ply combines a low density syntactic core (hollow glass spheres) and structural fabric to create high panel rigidity in a rapidly laminating format. Zpreg is designed for production cycle times of around 15 minutes using compression moulding. No autoclaving is needed. Surface quality is high, and parts have enough structure to withstand the usual dings and dents. Resins provide a stable surface finish with very low shrinkage. Finished parts, such as fenders, bonnets, roof tops and boot lids, accept all standard types of paint. The cost of an aluminium tool for a fender would be around £50,000, and could be as little as half of that. This compares favourably with the £600,000 needed for a toolset for a pressed steel part or the £250,000-plus for an injection moulding tool. Processing temperatures are 85-180[degrees]C. ACG supplies the materials system and process knowhow, but does not manufacture parts.