K 6 Hall, Booth A75
The future of the car body is lightweight, thus making a contribution to saving energy in transport. At the same time they must be very stiff, so that the vehicle receives the necessary stability. A new concept of Bayer MaterialScience the design of the car cover addresses these requirements and also fulfills the dream of drivers for smooth, high quality finishes. With the development of parts in sandwich construction, the company now treading new ground in line with the nature.
At the K-show 2013, Bayer, the company exemplifies a tailgate cover before, during whose development was the natural inspiration - and that in two respects. "With a sleek, compact outer skin and a foamed core, the construction of the component much resemblance to a bone," explains Ulrich Grosser, Advanced Technologies team leader at Bayer MaterialScience. The construction of this highly rigid and lightweight at the same part of the body is due to a long evolutionary development. However, the similarities end at the production of the parts: While natural bone to grow through cell attachment, are accessed in the development of sandwich parts back to methods of processing plastics.
"Continuous glass fiber scrim For the outer layer impregnated with a thermoplastic polymer based on polycarbonate," said Grosser. "The wetting and coating of all fibers is ensured by the plastic matrix." This was the key to the high stiffness of the outer layers of the sandwich structure. Shrinkage of the polycarbonate blends such as "Makroblend" is very low and the sandwich structure has a very smooth, high quality surface. For the desired look that can then be painted - for example with coatings based on polyurethane raw materials.
Light weight with good insulation
In a second step, the top and bottom of the tailgate lid are assembled and the resultant cavity completely with the polyurethane foam system "Baysafe". The foam has a very low density and gives the component a by special light weight. Since the foam is also very stiff and glued around the outer surface, the component also shows a low susceptibility to minor damage.
In the event of an impact the foam serves to absorb energy and thus safety of occupants and passers-by. It is highly heat insulating and thus makes an important contribution to energy management in the vehicle: The air conditioning and heating can run on lower level and consumes less energy. This also allows fuel consumption and CO2Reduce emissions. In this conserves battery electric vehicles and increases the action radius of the vehicle. Thanks to its sound insulation of the foam also ensures peace in the cockpit.
In addition, the foam can be also a particularly efficient and sustainable manner is embed antennas. Unlike metal parts, the polymers allow undisturbed reception over a wide frequency range. Other features to lighting can be integrated into the sandwich component.
How to Beat a permanent tree roots
The prototype exhibited at the show is a prime example of the high degree of design freedom that the plastics from Bayer. To enable a realistic use of the conceptual part of the vehicle, the company has also developed an intelligent solution for attachment to the vehicle body. "Here again, nature has proven to be the best builder," said Grosser. The task consisted in a robust and durable connection of the hinge with the lightweight structure of the tailgate cover. "We have looked at how trees are anchored on forest soils," explains the team leader. "A branched root system also gives large and heavy trees a secure grip on the often soft soils."
For a realistic solution, the researchers optimized the appearance of the hinge mount with the help of CAE calculations. As a result, the plastic structure has a striking resemblance to the appearance of a braided tree root on the forest floor. Experiments show that the hinge attachment can be mounted easily and is very firmly in the lightweight foam core.
Noble sandwich components for high-quality products
"With these material specific construction milestone, we succeeded in the efficient production of sandwich panels," says Dr. Olaf Z√∂llner together the recent developments. The Head of Application Technology for polycarbonate provides said body part, but only as an example of very many possibilities offered by the new technology: "These light and rigid composites of polycarbonate blends are very suitable for the construction of some of Ultrabooks, and other high-tech products, "said publican. Also in the furniture manufacturing and many other applications, there would be promising prospects. "The auto industry is often a pioneer in groundbreaking technical developments. But we also look forward to the conversations with customers and partners in other industries. "