The new composite materials are based on “large-tow” carbon fibers, which consist of a bundle of 50,000 individual filaments (50K) and yet comply with the high mechanical requirements of the aerospace industry. Previous fiber composites in aerospace have typically been based on carbon fiber bundles of 12,000 or 24,000 filaments.
The new thicker fiber bundle type offers the advantage of more efficient fiber production and economies of scale through the whole value chain, up to the finished components. The range of possible components lasts from the wings, to the tail unit, to components in the fuselage of aircraft on a large scale.
SGL Carbon has developed an advanced large-tow carbon fiber, with high-tensile strength and stiffness (Intermediate Modulus/IM). For this purpose, the company has adapted its own raw material (PAN precursor), produced in Portugal to comply with the requirements, and has also modified the fiber carbonizing process at Moses Lake, USA and Muir of Ord, Scotland.
10 years ago, large-tow carbon fibers were still thought of as simple industrial fiber. Since then, the quality has improved dramatically. The fibers have proven themselves in mass-production processes in the automotive sector and other industries. With our new 50K IM fiber, we’ve now brought this achievement to aerospace standards for the first time.
Dr. Andreas Wöginger, Head of Technology in the Composites - Fibers & Materials business unit at SGL Carbon
SGL Carbon is now working together with Solvay to bring composite materials based on the new fiber to the market. This is a forward-looking decision: In the aerospace industry, fiber composites are a billion euro business, which will continue to grow in the years ahead.
“The potential for improvements in efficiency is huge. Together with our partner Solvay, we’re offering customers an extremely interesting prospect for promising further development of lightweight construction in the aerospace industry, against the backdrop of increasing volumes combined with high cost pressure,” says Dr. Andreas Wöginger, Head of Technology in the Composites - Fibers & Materials business unit at SGL Carbon.
The cooperation between SGL Carbon and Solvay has many advantages for both partners. SGL Carbon benefits from Solvay’s expertise in resin formulations as well as its extensive aerospace expertise and hopes to accelerate growth with use of materials for the aerospace industry. For Solvay, this close and exclusive cooperation with a large-tow fiber manufacturer represents an opportunity to work together for the first time on optimizing the surface of the carbon fiber for bonding to the resin system, thus creating further added value for customers.
The cooperation between Solvay and SGL Carbon will start by focusing on the qualification of the fiber as well as of the thermoset and thermoplastic composites produced from it. Currently, various aircraft manufacturers are testing the new materials for use in one of their programs, ideally soon to allow or possibly even to prescribe their use to their suppliers. The first interim results and discussions of the tests are looking promising.
Independent of the cooperation with Solvay, SGL Carbon already offers a wide range of prepregs and textile fiber semi-finished products for non load-bearing aerospace applications such as interior components. In the small aircraft, helicopter and air taxi sector, SGL Carbon’s portfolio even includes all services from engineering to the finished component.