Carbon fiber is one of the most exciting materials being used to make fast race cars. The more carbon fiber race teams use, the faster their cars get. And yet, some teams are discovering they can do better by embracing plant fibers. That’s right, we have entered the era of plant and carbon fiber materials being married on the racetrack.
Exhibit A is the new Porsche 718 Cayman GT4 Clubsport. The car recently made its debut in Daytona with doors and a wing that looked like carbon fiber at first glance. Yet close inspection revealed they were not carbon fiber at all. Rather, the parts were made from flax.
Flax has been used for centuries to create a variety of different things. If you have anything in your house that is genuine linen, it was made with flax fibers. Those same fibers can be mixed with epoxy resins to create composite materials similar to carbon fiber.
Flexibility and Strength
One of the primary structural benefits of flax fiber composites is that they are more flexible. This added flexibility makes the flax product better at dampening vibrations. Why does this matter for racing cars? Because carbon fiber parts shatter when cars crash. Flax fiber parts do not.
The downside of the additional flexibility is a loss of strength. Flax fiber composites are not nearly as strong as their carbon fiber counterparts, so they aren’t usable for applications requiring greater structural integrity. Porsche is currently using the flax composite to make door panels and wings. It’s unlikely they would try to make an entire car body from the material.
Sustainability and Recycling
Porsche says the driving force behind their flax fiber project is sustainability. For starters, flax fiber composites can easily be shredded and used to create new parts. Carbon fiber can be shredded as well, but recycled carbon fiber loses a lot of structural integrity, explains Rock West Composites.
Greater sustainability is also realized in terms of production. Porsche says they can create their flax fiber composite with 75% less energy than it takes to produce carbon fiber. That is pretty amazing. Again, Rock West Composites explains why this is important.
According to Rock West, the tremendous amount of energy required to produce carbon fiber is the single most important factor contributing to its high price. The composites industry has been working for years to reduce costs by somehow reducing energy consumption.
Taking it one step further, less energy use is considered a benefit to sustainability. If Porsche isn’t burning as much fuel to produce flax fiber composites, they are not contributing as much to the detrimental effects of producing power. They are also leaving more energy on the grid.
Taking It to the Streets
For now, marrying flax fiber composites with carbon fiber is something Porsche will save for its racing cars. While they do intend to eventually deploy their new composite in street vehicles, they say that they are still years away from doing so. They will use the next few years to test the composites on racing hoods, fenders, wings, and doors.
As production and design mature, Porsche also hopes to bring the cost of their flax fiber composite down. It is still more expensive than carbon fiber despite using so much less energy to produce it, but Porsche expects to change that over the course of time. We will see what happens.
And there you have it. A new composite material that can be married with carbon fiber in the automotive sector. It’s fascinating to think of the possibilities that lie in store.