In the ongoing search for new ways to reduce vehicle weight, automotive OEMs and tiers have been looking for a better alternative to steel, aluminum and thermosets for large, aerodynamic, horizontal body panels. SABIC Innovative Plastics and Azdel, Inc. have launched their new hybrid thermoplastic composite grade, IXISÒ 157 composite, a continuous glass-fiber-reinforced sandwich composite for automotive horizontal body panelsIXIS 157 composite is the first product launched using high performance thermoplastic composite (HPPC) technology - and provides critical advantages over traditional materials, starting with a 50 percent weight reduction compared to steel. By adopting IXIS thermoplastic composites, automakers can design cost-effective, lightweight and aerodynamic body panels that will help drive the success of fuel-efficient future models.
The IXIS composite is composed of a random glass fiber reinforced core with a glass content (by weight) of approximately 50 percent, together with a 0º/90º skins of continuous unidirectional fiber reinforced thermoplastic. The skin material enables a Class A paint finish and dimensional stability, while the core material aids processing and reduces overall material costs. IXIS composites are significantly lighter in weight than steel and thermoset resins, with the potential to make a large contribution to improved fuel efficiency. They also offer important performance benefits, including excellent sound-deadening qualities for a quiet ride and outstanding damage resistance. In comparison to thermosets, which tend to shatter and splinter on impact, and steel, which tends to crumple, IXIS composites rebound, offering better energy absorption for pedestrian safety.
The polypropylene-based 157 grade is designed for off-line painting, and the upcoming 200 grade is intended for online painting and processing through the e-coat process. Both can be recycled. Thanks to a good polymer/glass fiber bond, the material can be granulated and remolded into other engineering applications. Unlike steel, IXIS composites enable part integration, such as the insertion of antennas into the roof of a vehicle. Although thermosets have been used in this manner, they are heavier and far more difficult to recycle.
IXIS composites offer a compelling weight advantage over steel, but that is just the beginning. They are designed for low-pressure compression molding - a low-energy process - less costly aluminum tools can be used. All these factors add up to a very attractive economic value for automakers and tiers.
Fiber-reinforced composites are a widely used technology for the aviation and aerospace industries. With their long history of breakthrough ideas, SABIC Innovative Plastics and Azdel have adapted this technology for automotive applications by leveraging the dimensional stability and high-quality surface finish of continuous, unidirectional glass fiber. In contrast to cut fibers, continuous fibers inhibit thermal movement, helping to reduce expansion and contraction of large, horizontal parts when exposed to sun and temperature extremes.