Researchers at the Department of Energy’s Oak Ridge National Laboratory have demonstrated a production method they estimate will reduce the cost of carbon fibre as much as 50% and the energy used in its production by more than 60%.
After analysis and successful prototyping by industrial partners, ORNL is making the new method available for licensing.
High cost has been the single largest roadblock to widespread use of carbon fibre as a strong, stiff reinforcement for advanced composites. ORNL’s new lower cost method builds on over a decade of research in the area. The researchers’ success promises to accelerate adoption of carbon fibre composites in high-volume industrial applications including automobiles, wind turbines, compressed gas storage and building infrastructure.
More than 90% of the energy needed to manufacture these advanced composites is consumed in manufacturing the carbon fibre itself. Reduction in energy consumption in manufacturing will enable earlier net energy payback—that is, the energy savings gained in using products made from lighter-weight material compared to the energy consumed in making the material. Similarly, ORNL is working as a technology partner at the IACMI to enable the use of low-cost carbon fibre composites in a wide range of next-generation clean energy products.
Carbon fibre is produced by converting a carbon-containing polymer precursor fibre to pure carbon fibre through a carefully controlled series of heating and stretching steps. In current commercial practice, the precursor, polyacrylonitrile or PAN is chemically modified and optimised to maximise the mechanical properties of the end product. The high cost of specialty precursor materials and the energy and capital-intensive nature of the conversion process are the principal contributors to the high cost of the end product.
Acrylic fibre of similar chemistry, however, is produced on a commodity basis for clothing and carpets – a high-volume product that costs roughly half as much as the specialty PAN used in the carbon fibre industry. ORNL researchers believed textile-grade PAN was a pathway to lower-cost carbon fibre, but laboratory-scale experiments couldn’t fully explore its potential at a production scale.
Extensive mechanical property tests have been performed on carbon fibre from the new process, and several auto manufacturers and their suppliers received quantities suitable for prototyping, with encouraging results.
Gary Jacobs, ORNL’s interim associate lab director for Energy and Environmental Sciences said;
Our R&D into process improvements and the extensive validation work at the Carbon Fibre Technology Facility provide manufacturers and end-use industries the confidence needed to invest in large-scale manufacturing, knowing there will be a market for this material.
Companies, including licensees of the new method, will be able to use the Carbon Fibre Technology Facility to refine and validate the carbon fibre manufacturing processes. ORNL will accept license applications for this low-cost carbon fibre process through May 15. Licensing information for manufacturers in the U.S. is available here.