A car’s crash components can spell the difference between life and death. Their job is to absorb energy in a collision in order to protect the driver inside. Researchers have now found a way for the automotive industry to mass-produce a particularly safe class of materials known as thermoplastic fi ber composite components.

Vehicles used to be predominantly made of steel. However, this raw material has long faced stiff competition from other materials, and modern cars are now built from a mixture of steels, aluminum and fi ber-reinforced plastics. Highly stressed load-bearing structures and crash components that are designed to buckle on impact help to reinforce the body in order to protect the vehicle‘s occupants in the event of a collision. Automakers have previously constructed these parts from composites using a thermoset (i.e. infusible) matrix. But this approach has a number of disadvantages: as well as being diffi cult to implement effi ciently in a mass production environment, it can also be potentially hazardous since this material tends to »delaminate« into sharp-edged splinters in a collision. A further problem is the fact that thermosets cannot be recycled. Researchers from the Fraunhofer Institute for Chemical Technology ICT in Pfi nztal have now found a solution to this problem by developing a new class of materials designed for large-scale use in vehicle construction: thermoplastic fi ber composite materials. Once they have reached the end of their useful life, they can be shredded, melted down and reused to produce high-quality parts. And they also perform signifi cantly better in crash tests: thermoplastic components reinforced with textile structures absorb the enormous forces generated in a collision through viscoelastic deformation of the matrix material – without splintering.

Researchers had previously failed to come up with a suitable manufacturing technique for thermoplastic composite structures made from high performance fi bers, but the ICT engineers have now developed a process suitable for mass production which makes it possible to manufacture up to 100,000 parts a year. »Our method offers comparatively short production times,« states Dieter Gittel, a project manager at ICT. »The cycle time to produce thermoplastic components is only around fi ve minutes. Comparable thermoset components frequently require more than 20 minutes.«

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• Making vehicles safer