As demand for high-strength FRP parts increases, companies are seeking suppliers to help them develop and shape their processes and create value. Nowhere is that more evident than in the automotive industry, where composite mass production is still in its early stages. Automation will play a crucial role in the future of composites within this industry, since reducing processing costs and speeding up production are critical for gaining acceptance.
Steve Larby, Henkel’s director of composite process development, spoke about the growing use of composites as a response to market megatrends at a recent CAMX educational session. “Market drivers include global trends in population and GDP growth, sustainability and energy costs, among others,” said Larby. Industry trends are affected by a number of factors, including the high demand for travel, lightweighting, the desire for comfort through noise and vibration reduction, and the need to reduce costs. The outcomes, Larby said, are new designs, new materials, new processes and scalable production.
Larby estimated that the use of structural composites has reached a market penetration level of 100 percent in the wind energy industry, 50 percent in the aerospace industry and just 10 percent in the automotive industry, where mass production is rapidly developing. Prepreg hand layup works well for prototype production of automobiles in annual units under 1,000, but production in the moderate range of 30,000 and high range of more than 100,000 units per year will require other processes such as infusion resin transfer molding (RTM), prepregs with automatic tape laying (ATL) or advanced fiber placement (AFP) with oven vacuum bag cure or vacuum infusion. Both ATL and AFP require significant capital investment.
Using its polyurethane-based composites matrix resin called Loctite Max 2, Henkel is providing competitive advantage for its customer, Daimler, in the production of a composite leaf spring – a suspension part – that is lighter than steel by 65 percent while still providing high durability. The spring is produced using RTM. The preforms are cut, assembled and loaded into the press by robotics. Injection time is relatively fast, as is the cure time since the polyurethane cures more rapidly than epoxy. A similar project, the leaf spring for the Volvo XC90 crossover vehicle, will begin production in the first quarter of 2015 and is expected to deliver a weight savings of 4.5 kilograms over steel springs.
Automotive exteriors also offer automation potential for structural composites. Henkel is helping to reduce the manufacturing costs of a roadster roof with its urethane resin and internal release agent. The rapid turnaround of the part using surface-RTM delivers a mold surface ready for immediate painting. The molding cycle lasts between 5 and 5.5 minutes, enabling the production of nine moldings per hour, a substantial improvement over the incumbent roof part using an epoxy-based matrix.