The R&D team didn't pick any old part as their first to test out the new material and system. They produced a side impact beam, usually made of high-strength steel, which must withstand a lot, since its main job is to protect passengers during a crash. The prototype passed crash tests, absorbing more energy than side impact beams made out of either short glass-fiber polymer or metal. The material also weighs 40 percent less than ultra-high-strength steel, and maintained stiffness in a wide temperature range of -40C to 90C.
A combination of the design, materials, and processing is what made this possible. "This composite part is produced from organo sheet made from a continuous glass fiber and PA66 laminate," Glasscock told us. "The sheet is shaped into the beam in a heating and forming process which also crystallizes the material. Next, the steel connectors are inserted and the component is back molded with DuPont Zytel nylon."
To help improve the Fiat Punto car's mechanical performance, DuPont co-developed a jounce bumper system that integrates multiple components and also cuts cost. The job of a jounce bumper, part of the car's shock absorber system, is to reduce noise and vibration, and absorb impact from shocks. It also makes it easier for drivers to recover from and maintain control when encountering rough roads or small obstacles like potholes.
Using finite element analysis, DuPont modifed a grade of its Hytrel thermoplastic elastomer to develop a design that could be tailored to Fiat's specs, including force displacement curves. Compared to jounce bumpers made of more typical foam polyurethane or rubber, the new component built with the new material showed better durability and elastic recovery, and lower variation in stiffness due to temperature changes. Road tests showed performance similar to bumpers made with polyurethane, but with much less damage.
The company will showcase all of these technologies at the K-Show 2013 conference in Germany this fall, October 16-23.