Using unidirectional glass tapes to improve impact performance of thermoplastic composites in automotive applications

With strong pressures to reduce carbon emissions and improve fuel economy for passenger vehicles and commercial trucks in most geographies, interest in composites by transportation OEMs is growing. As a result, suppliers of composite materials are working to improve thermomechanical performance, increase processing speeds, reduce part mass and costs, enhance surface aesthetics with fewer post-mold operations and generally make it easier to position composites against high-strength steel and aluminum. To that end, a study conducted by organizations in Europe and North America last year looked at methods to increase stiffness/strength and impact resistance of thermoplastic composites by using continuous-strand, unidirectional-glass (UD) tapes to produce woven fabrics as well as laminates. Combinations of the tape fabrics and the tape laminates in various layup patterns were then used in conjunction with charges produced in the direct-long-fiber thermoplastic (D-LFT) inlin e compounding (ILC) process to compression mold both test plaques and later an actual automotive underbody-shield part to determine the extent to which impact performance could be improved.