Orlando, Fla. — In recent years, the push for lightweight solutions and the new forms of mobility that have emerged — powertrain electrification, alternative fuels, autonomous driving — have changed and are still changing the material requirements of the automotive industry.
Lanxess Corp. is one of the companies that has been steadily responding to these new needs with the development of material solutions that can help tackle some of the challenges that arise, says Jose Chirino, technical director of Americas for Lanxess' high-performance materials unit.
At the Lanxess booth at NPE, one of the main highlights was the all-plastic brake pedal made from high-modulus Durethan BKV60H2.0EF and Tepex dynalite composite sheet. While the brake has been showcased at various events in the past, the important message, Chirino said, is that "we are reaching mass production volumes on Tepex applications."
"It's evolving. While the first application was in the Porsche 911 Carrera, it's now being used in high-volume vehicles. You might say we are seeing the democratization of the Tepex technology," Chirino explained.
Tepex is a continuous fiber-reinforced thermoplastic composite that combines stiffness and impact resistance with extremely low weight. Due to the flexible fiber orientation of the materials, it can be tailored to specific applications, including structural components such as front-end modules. Thanks to its energy absorption properties, it has also been used in underbody panels, replacing the heavier SMC material conventionally used.
Another structural part in which Tepex has been used is the battery holder.
"This yields a 30-50 percent reduction in weight vs. the metal that is traditionally used," Chirino said.
In hybrid and electric vehicles, weight reduction is especially important to maximize mileage range. He pointed to a structurally reinforced front end with integrated active grille shutters (AGS) at the booth that provides weight reduction while also improving engine thermal management and vehicle aerodynamics.
"It improves the drag of the vehicle," he explained. "The shutters are closed when the car starts and the engine is cold. They then open, depending on the speed, to cool the engine if necessary. If not, they close, as unnecessary air entering the engine bay adds aerodynamic drag to the car, and the higher the speed, the higher the aerodynamic drag. Reducing drag improves the fuel efficiency of the car."
The push for lightweighting is also reflected by the fact that car engines are getting smaller, he said, which is causing the temperatures to become hotter under the hood. The company has developed a new heat stabilization system called XTS2 (Xtreme Temperature Stabilization) for nylon 6/6 variants of Durethan at NPE2018. This system is able to withstand long-term temperatures of up to 230° C, providing an alternative to costly high-heat specialty thermoplastics, such as fully or semiaromatic polyamides or polyphenylene sulfide.
The first grade from the XTS2 product range is Durethan AKV35XTS2, a nylon 6/6 reinforced with 35 percent glass fibers by weight, which has a considerably better long-term heat aging performance when compared to nylon 6/6 with a standard copper-based stabilizer.