Researchers at Montana State University (MSU) in the US have developed ‘stretched’ carbon fibers that they say are more formable but have the same strength as conventional fibers.
The relative stiffness of traditional carbon fiber composite makes it harder to form into aerospace parts such as a wing without expensive machinery, they clam. It also sometimes requires a metal substructure that can be subject to corrosion.
The scientists’ carbon fiber is created by stretching the material so that some of the fibers break at natural weak points using a tool called the Bobcat Head. It works by passing a flat strand containing thousands of individual carbon fibers through a series of rollers and applying force to break the fibers where there are nicks and other imperfections. Only about 2% of the fibers are broken across a given area, according to Douglas Cairns, who is leading the project.
He says that the material is around eight times more formable while being roughly the same strength. That means the material can be shaped with simpler equipment and without a metal substructure.
The researchers plan to scale up the tool for a pilot demonstration. The project has been funded by a total of US$25.8 million in contracts from the US Army.