Lightweight PP and plastic-metal hybrid solutions on show at Germany’s VDI congress
30 March 2017
With the automotive industry’s continued focus on reducing emissions and increasing fuel efficiency, materials-maker SABIC is presenting a range of solutions at this year’s VDI Plastics in Automotive Engineering Congress in Mannheim, Germany.
The solutions cross a range of application segments – from a vehicle’s exterior and glazing to components like instrument panel carriers and structural reinforcements for the body-in-white (BIW). Combined, these solutions can potentially reduce the overall weight of a vehicle by 13 to 15 kg.
“Our featured solutions at this year’s VDI Congress bring forward some novel approaches or highlight progress in other technologies,” said Scott Fallon, global leader of SABIC’s automotive business. “I especially like that we’re showcasing answers for the industry that can ease multiple pain points. They not only help OEMs shed weight. They add value in other ways, too.”
A good example of this is plastic-metal hybrid (PMH) structural reinforcements for the vehicle’s BIW. A PMH floor rocker reinforcement, for instance, can help reduce weight by up to 45 percent vs. an all-steel alternative. In this component, NORYL GTX resin (mPPE/PA) from SABIC combines with steel to form a very efficient energy-absorption crash box structure. This saves 1 kg in weight and maintains the required level of crashworthiness.
The component is an industry-first use of plastic in a BIW reinforcement without the use of structural adhesives or foams. Use of the NORYL GTX resin allows the part to go through the automaker’s e-coat process with the rest of the BIW. Additional opportunities across the BIW means that a manufacturer could save up to 8 kg of weight with these hybrid solutions vs. all-metal reinforcements.
SABIC is also featuring an injection-molded, foamed instrument panel carrier. The part uses the company’s STAMAX long glass fiber polypropylene (LGFPP) resin (60YK270E grade) with a block copolymer SABIC PP resin (612MK10EE grade) in a structural foaming process.
In this approach, the manufacturer injects the material into the mold with a foaming agent. Immediately afterwards, the mold is opened a few millimeters, controlling the final density of the part. During the process, the foaming agent produces CO 2 bubbles that create a foamed core. The final produced part is both light and stiff. SABIC’s solution is emission-optimized and meets the VDA278 industry standard. Other potential benefits from this foamed STAMAX resin solution include the need for less material during processing, shorter cycle times, and a better balance of impact and stiffness.
Another PP-based solution from SABIC on display is a lightweight, thin-wall front bumper on a recently launched 2017 model. This part uses SABIC PP compound (8650 grade) to optimize the thickness to 2.5 mm, which can save more than 10 percent in weight. Low shrinkage, excellent impact-stiffness balance and potentially reduced cycle times are among the advantages of this approach. SABIC’s material is an open compound, which allows for greater dimensional flexibility for molders.
SABIC continues to highlight progress in plastic glazing applications. This time, the featured part is an in-production rear quarter window, the largest in the world in LEXAN polycarbonate (PC) resin (GLX143 grade). A two-shot injection compression molding process combining PC resin with CYCOLOY PC/ABS alloy (XCM830 grade) results in a final part that is up to 40 percent lighter vs. conventional glass. This glazing solution allows for design features not possible in glass, as well. Notably, this window is the first from a new production facility in China devoted to the manufacture of mass-produced LEXAN PC glazing parts.
Finally, SABIC is highlighting ongoing development work in the use of unidirectional laminates. The idea is to combine the material supplier’s UDMAX tape with STAMAX LGFPP resin to achieve further weight reduction, while improving mechanical performance. UDMAX tapes are fiber-reinforced thermoplastics, which offer high strength and stiffness, good processability and fatigue resistance.