Lightweight composite materials have been a key part of developing more fuel-efficient vehicles, as data from the Department of Energy’s Vehicle Technologies Office indicates that a 10% reduction in vehicle weight can lead to a 6% to 8% improvement in fuel economy. However, as vehicle component manufacturers have found new ways to shave off weight, they’ve also learned to maximize composites’ other notable characteristics, including their tremendous strength and moldability.
But the tempting design freedom that CFRP and GFRP materials offer has been challenged by production scalability. That too is beginning to change. Developers are focusing on simplifying the number of components to assemble and reducing the need for secondary assembly or finishing to speed the entire manufacturing process at a more competitive cost.
That work seems to be paying off. Research firm Global Market Insights projects that the automotive composites market will grow at a compound annual growth rate of more than 6.7% from 2020 to 2026. Much of that growth will be due to work building off innovations now coming to market, such as the four composite applications profiled here.
Simplified Trunk Floor Production
The Hyundai Creta, India’s top-selling SUV, makes ample use of lightweight carbon fiber, from its front fender to the passenger seat cowl. However, it’s the SUV’s trunk floor that pushes the envelope in the use of composite materials.
When Brazil-based Tier 1 automotive supplier DPA Moldados began looking for a thermoplastic sandwich core solution to replace its previous thermoset option, it turned to EconCore, a specialist in thermoplastic honeycomb core technology, to help. Together, the material and component suppliers developed a compression molding process that replaces the conventional use of a multi-step thermoset polyurethane, glass fiber, paper honeycomb sandwich lay-up with a low-cost and environmentally-friendly thermoplastic honeycomb alternative.
In the past, such modular trunk floors were made out of two or three molded parts that were then connected into foldable sections with a hinge – yet another separate piece. With the new process, the supplier extrudes a thermoplastic material that is directly converted into the honeycomb core. The core is compression molded with thermoplastic glass fiber mat composite skins, all from a single sheet of sandwich preform, and the decorative thermoplastic carpets are added on the surface of the part at once. The hinge connecting the foldable sections is created in the same process by accommodating a mold gap design. The soft, preheated thermoplastic honeycomb core is calibrated into a “V” profile, creating a living hinge.