The use of carbon-composite components continues to be an extremely effective solution to weight saving in very high-end premium cars, but its cost continues to limit its application in higher-volume vehicles. Now, Prodrive—whose composites were incorporated into several of the cars launched at the Geneva Motor Show—has developed an innovative process to help reduce cost.
The company has focused on achieving simpler fixing integration via the elimination of costly bonding of clips, fasteners, threaded inserts, and hinges to provide easier, more robust assembly for interior applications without any reduction in finish quality.
Gary White, Prodrive Composites’ Engineering Manager, said: “We are making composite components more affordable by reducing the cost of manufacture, not just of the component itself but also by addressing wider assembly issues. By taking a look at the bigger picture, we think we can help bring the benefits of composites to a larger market more quickly.
“Features normally added in a separate operation, such as clips and inserts for threaded fasteners, can now be molded directly onto the back of high-quality composite panels, producing a more cost-effective part than a conventional bonded assembly, and one with greater mechanical strength. The process removes a major barrier to the wider use of composites.”
Historically, composite components have demanded extensive manual input, including layup and hand trimming operations, leading to increased process times and subsequently higher costs. This can be reduced by increased use of automation.
White says Prodrive has unlocked “a number” of efficiency improvements by introducing a new process that combines a plastic back-injection molding to house complex fixtures and fittings via a press-molded component.
“The resultant component is around 60% the cost of one made using a traditional method—but is visually identical,” he said.
Prodrive has started manufacture of parts for two production applications, both premium automotive interiors.
“One of the challenges of using carbon composite panels is the provision of fastenings for their attachment, which can lead to costly, intricate components,” said White. “Conventional solutions involve creating a complex carbon shape to carry the fittings. By molding onto the finished composite, we can match the convenience of an injection-molded plastic part at a fraction of the cost, while providing the low weight, strength, and superb display surface of carbon.”
As well as being a very high profile motorsport constructor, Prodrive provides design, development, and manufacturing support for a wide range of transportation technology; its specialist manufacturing areas include carbon composites and ultra-high precision small batch machined components. Its design capability sees it working with European and U.S. OEMs, focusing on, inter alia, vehicle dynamics, power electronics for HEVs, and precision actuator systems such as active aerodynamics.
In most automotive applications, the company supplies OEMs directly and is able to meet requirements that include very high-quality finish for prominent interior surfaces, said White: “Cosmetic perfection on all exposed surfaces is essential and it has to be sufficiently durable to cope with use and conditions across the world. We validate this by the application of environmental and climatic tests to ensure durability even in the most demanding climates. Parts made using our new process have passed the full range of OEM tests, and we are now ramping up to supply production vehicles.”
Innovations by Prodrive, such as its new molding process, are seeing growth in its carbon-fiber business, but the drive to keep costs down continues. A significant aspect of this is to operate as the engineering partner for vehicle manufacturers.
“But improving efficiency requires providing much more than just components,” stressed White. “We have established processes that allow composites to be used more effectively. In 2009, we launched the lacquer-free finish that resists stone chips and UV deterioration. Earlier this year we launched colored composites. And now we have integrated molded plastic features onto composite panels. Collectively, these developments contribute to the creation of more competitive products, which means widening the scope of carbon-fiber applications.”