Why Curing is the Next Big Hurdle for Composite Fabricators


Composite manufacturing companies have no illusions of landing a major auto manufacturer as a client. They know that the chances of selling large volumes of carbon fiber fabric to be made into car bodies is slim. Why? Because such an extensive use of carbon fiber would cost too much.

The realities of composite fabricating prove that there are still hurdles to overcome. Just five years ago, the big focus was on recycling. It paid off. Car companies are now making greater use of recycled carbon fiber for noncritical components that do not require the kind of strength virgin materials offer.

With recycling now on its way to maturity, the industry’s next hurdle is curing. The process now being used is too time-consuming and expensive. Find a way to overcome those issues and the automotive industry will go all-in on carbon fiber car bodies.

How We Do It Now

Creating a carbon fiber car body with current technology requires a manual layup process and autoclave curing. Fabricators create a tool (mold) to accept multiple layers of resin-infused carbon fiber fabric. The fabric is layered in the tool until the desired thickness is achieved.

At that point, certain processes are applied to ensure that the material is evenly impregnated and free of air bubbles. Then the entire assembly is sent to an autoclave where high heat and pressure cure the resin to create what is known as a carbon fiber reinforced plastic (CFRP).

Understand that an autoclave is essentially a giant pressure cooker. One capable of handling the larger parts of a car body would have to be at least as big as a commercial walk-in cooler. If a fabricator wanted to go larger, you might be looking at one as big as a two-car garage.

Excessive Energy Use

Autoclave curing works effectively enough. Its greatest weakness is the amount of energy an autoclave consumes. And as you know, energy is not cheap. The bigger the autoclave, the more expensive it is to run.

At this point you might be thinking that autoclave curing might not be necessary. You base that on the knowledge that hobbyists create carbon fiber parts at home without an autoclave. Just remember this: hobbyist parts fabricated in the garage do not need to offer the same kind of strength and rigidity required of commercial parts.

Moreover, hobbyist parts are generally much smaller. They cure much more readily at ambient temperatures. Panels large enough to be used in car bodies would take so long to cure in ambient temperatures that it would be economically infeasible to work that way.

Solutions on the Horizon

Curing is the next big hurdle for the composites industry because it is key to expanding markets. Eliminate the need for autoclave curing and you suddenly have a bunch of new customers ready to buy. To that end, there are solutions on the horizon.Custom composite manufacturing companies like Rock West Composites are busy working on a solution.

One interesting area of research combines carbon nanotubes with electricity to create a composite material that cures in minutes without the need for high heat and pressure. That research is promising. It could be ready for widespread market use in a couple of years.

Another possibility is developing better 3D printing techniques utilizing new resins that cure in place. Find a way to do print effectively and you open the door to fabricating extremely large parts in situ. Think car bodies, airplane wings, and watercraft hulls.

Curing inefficiency is a problem the industry can overcome. It is just a matter of time before they do. And when that time comes, watch out.