A polyester-based sheet molding compound (SMC) that realizes a Class A surface and incorporates glass beads for further weight reduction has delivered a 20-lb. (9-kg) weight saving to the 2016 Chevrolet Corvette Stingray Coupe model. This represents the first production use of TCA Ultra Lite from Continental Structural Plastics (CSP, Auburn Hills, MI).

TCA was formulated to eliminate the occurrence of paint pop defects in automotive OEM paint lines while improving the overall surface quality of the part.  This goal was accomplished via the development of a new polyester resin chemistry that makes the SMC substrate tougher by resisting cracking between filler and glass fiber components.  This patented technology has been extremely successful and has reduced paint-related defects by up to 98 percent throughout the manufacture of Class A body panels at multiple OEMs.

In the latest development, "Through a joint continuous improvement effort, Chevrolet and CSP have significantly reduced the density of the Corvette body panels - from 1.9 specific gravity for the 2013 model year, to 1.6 specific gravity for the 2014 model year to 1.2 for the 2016 model year," said Christopher Basela, Lead Engineer for Corvette Body Composites.

The mass savings afforded by TCA Ultra Lite is accomplished through the use of a CSP-patented technology that uses treated glass bubbles to replace a portion of the calcium carbonate filler, resulting in a lighter density material. A total of 21 body panel assemblies, including doors, decklids, quarter panels and fenders, are molded from TCA Ultra Lite in the 2016 model.

"In materials engineering, shaving a single pound per car is a significant accomplishment, so saving 20 pounds per car is monumental," said Tadge Juechter, Corvette Chief Engineer. "This is a great example of how Chevrolet is continually looking for innovations that improve performance on Corvette, and could benefit possible future applications."

When combined with CSP's patented vacuum and bonding manufacturing processes, TCA Ultra Lite offers a premium Class A finish with paint and gloss qualities reportedly comparable to metals, including aluminum. The material is able to withstand the high temperature E-coat process, and passes all OEM paint tests. It also reportedly offers reduced costs at all volumes - and for production volumes under 150,000, tooling costs for composites can be as much as 50 to 70 percent less than those for stamping steel or aluminum.

"We have been working closely with GM to launch this patented, weight-saving technology on the iconic Corvette, achieving this conversion with no changes in material thickness or tooling while maintaining the superior surface finish required for this premium vehicle," said CSP Chairman and CEO Frank Macher. "With this successful launch, we can say TCA Ultra Lite is proven to offer several advantages over aluminum, and is truly the next generation of lightweighting technology for the automotive industry."