Carbon and glass fibers reinforce synthetics so that they can be used for vehicle body construction. But in this regard, there is an abundance of potential found in natural fibers – obtained from hemp, cotton, or wood. If you combined bio-based textile and carbon fibers, you can obtain extremely light yet very sturdy components.
“Lightweight” is an important buzzword in automotive engineering, and just as important in the aerospace sector, too. Carmakers are increasingly counting on fiber reinforced synthetics. These fibers, which are embedded into the synthetic matrix, give the material its additional durability. Exactly which material you choose to use depends on its eventual application. Thus, primarily carbon fiber is used in Formula 1 racing. However, one drawback is its high price; even its processing can be tough. These are the reasons why carbon fiber-reinforced plastics (CFRPs) have still not yet found their path into wide-scale serial production so far to date. Glass fibers, on the other hand, are certainly reasonably priced, but heavy by comparison. But this may soon change, thanks to some new research approaches by researchers at the Application Center for Wood Fiber Research HOFZET of the Fraunhofer Institute for Wood Research, the Wilhelm-Klauditz-Institut WKI in Braunschweig.
Combining advantages, eliminating disadvantages
The scientists are relying on natural fibers of botanical origin. Variants derived from hemp, flax, cotton and wood are about as affordable as glass fibers, and moreover have a lower density than the pendants made of glass or carbon. Another advantage: If you incinerate them at the end of their life cycle, they produce additional energy – without leaving residues. Nevertheless, their durability and stability don´t reach that of carbon fibers. ”Depending on the application, we are therefore combining carbon with various bio-based textile fibers,” explains Prof. Dr.-Ing. Hans-Josef Endres, head of the Application Center for Wood Fiber Research. The fibers typically exist as fabrics that are placed on each other accordingly and are embedded by the plastic matrix. “We use carbon fibers in those areas where the part undergoes intense mechanical stress; in other areas, it’s natural fibers. This way, we can leverage the strengths of the respective fibers and get rid of the disadvantages to a great extent. ”The outcome: the parts are cost-effective, have a very high degree of durability, possess excellent acoustic properties and are substantially more ecological than pure carbon components.