For the two layup configurations shown, (b,c) fabricated sample of CF epoxy/PGS 70/CF epoxy composite, and (e,f) fabricated sample of PGS 70/CF epoxy/PGS 70 composite. (Image: NASA)

A team of inventors from NASA Langley and NASA Ames have created a new type of carbon fiber polymer composite that has a high thermal conductivity. This was achieved by incorporating Pyrolytic Graphite Sheets (PGSs) and Carbon Nanotubes (CNTs), which enhance the material’s ability to transfer heat when compared to typical carbon fiber composites.

Carbon fiber polymer composites are frequently used in aerospace structures because they are light, strong, and require minimal maintenance. However, they typically have poor thermal conductivity, which limits their use to applications where heat transfer is not required. Where heat transfer is needed, aluminum alloys are used instead, but they have drawbacks such as lower strength, higher weight, and increased maintenance needs compared to composites. The new material developed by NASA addresses this issue by combining the benefits of a carbon fiber composite with the high thermal conductivity of metal alloys.

NASA has also improved the composite manufacturing process to ensure better thermal conductivity not only on the surface, but also through the thickness of the material. This was achieved by adding perforations that enable the additives to spread through the composite. The process for developing this innovative, highly thermally conductive hybrid carbon fiber polymer composite involves several steps.

First, a CNT-doped polymer resin is prepared to improve the matrix’s thermal conductivity, which is then infused into a carbon fiber fabric. Second, PGS is treated to enhance its mechanical interface with the composite. Third, perforation is done on the pyrolytic graphite sheet to improve the thermal conductivity through the thickness of the material by allowing CNT-doped resin to flow and better interlaminar mechanical strength. Finally, the layup of PGS and CNT-CF polymer is optimized. Initial testing of the composite has shown significant increases in thermal conductivity compared to typical carbon fiber composites, with a more than tenfold increase. The composite also has higher thermal conductivity than aluminum alloys, with more than twice the thermal conductivity of the Aluminum 6061 typically used in the aerospace industry.

NASA is currently working on using this material for in-space applications, such as heat exchangers or radiators for removing carbon dioxide from the crew cabin atmosphere. On Earth, the composite could be used to create new radiators or heat exchangers for use in automotive or electronics applications.

NASA is actively seeking licensees to commercialize this technology. Please contact NASA’s Licensing Concierge at This email address is being protected from spambots. You need JavaScript enabled to view it. or call at 202-358-7432 to initiate licensing discussions. For more information, visit here .