Forged Composite: Tech. Department - Car and DriverCarandDriver said:In a word-association exercise, “Callaway” is probably equally likely to be followed by “golf” as “Corvette.” As it turns out, golf is now relevant in the car world, too, as Callaway Golf and Lamborghini have partnered to develop what they call Forged Composite, which could change the way carbon fiber gets deployed in cars. The only vehicle currently using Forged Composite is Lamborghini’s Sesto Elemento concept [shown below]. But compared with cars, the golf world has much shorter development cycles, which means you can experience this new material right now in Callaway’s Diablo Octane driver.
What is commonly called carbon fiber is actually carbon-fiber-reinforced plastic, a weave of thin fibers held together by a resin. It’s light—the body panels of a Corvette ZR1 are roughly one-fifth the weight of equivalent steel panels—and incredibly strong, at least in the direction it’s designed to take a load. Like a diamond, traditional woven carbon fiber is amazingly resilient on some load paths, correspondingly brittle on others; check out any modern Formula 1 car crash for an example of when this material goes wrong. Carbon fiber is also expensive, time-consuming, and labor-intensive to manufacture in large volume. Forged Composite promises to solve many of these problems.
How? Two words: discontinuous fibers. Forged Composite forgoes the weave and instead uses a random arrangement of loose fibers mixed with resin and forms them in a heated press at high pressure. The resulting composite is strong in all directions without the additional cost and complexity of adding multiple layers of material, as must be done with woven carbon fiber. If an indiscriminate arrangement of fibers has you worried about reliability, relax. Much of the work in developing Forged Composite was spent making sure the final product would be statistically consistent. An added aesthetic bonus of the random fibers is that each final product is as unique as a snowflake.
Alan Hocknell, Callaway Golf’s senior vice-president of research and development, says that from a manufacturing standpoint, Forged Composite is a godsend. The process makes it possible to form complex shapes in a single piece, with little or no wasted material, at tolerances as tight as one-thousandth of an inch. And it’s fast. The main structural tub in the Sesto Elemento spends only eight-and-a-half minutes in the press. Lamborghini says the same shape would take six hours using woven sheets preimpregnated with resin. Material costs are about the same as with woven carbon fiber, but since the manufacturing time is so much shorter (and less labor-intensive), Forged Composite is potentially cheaper to make and may better support high-volume production.
Forged Composite can be drilled (but not tapped) without the need to reinforce the area around the hole, so car parts can be joined together with through-bolts. The Sesto Elemento, for example, uses Forged Composite control arms. Bolt-on pieces such as suspension links and crash structures are the most likely places we’ll see Forged Composite on a future Lamborghini because those areas are easily adapted to existing architectures.
A roadgoing car made entirely of Forged Composite is still at least four years away, and even then, it will be very, very expensive—not just because it will have a bull on its badge but because anything made of carbon fiber is, and still will be, pricey. The manufacturing friendliness of Forged Composite means it should eventually trickle down to more affordable products, especially considering the fuel-economy benefits of lightweight materials.
Currently, Lamborghini is testing Forged Composite to see how it deals with extreme temperatures, corrosion, and long-term durability, as well as the stupid things owners are likely to do to the new material. But with extra horsepower offering diminishing returns, the folks in Sant’Agata realize that lightweight materials aren’t just for ever-tightening emissions standards—they’re also the next frontier in high performance.