Carbon nanomaterials in thin films enable cost and weight savings
Thin film uniformity and quality have a direct impact on performance and mission safety for numerous air vehicle platforms. Lack of uniformity in film materials could compromise a mission and, at the very least, drive life cycle costs to unsustainable levels. The ASI project eliminates these concerns through the establishment of improved performance film materials with lower weight and significantly reduced scrap rate.
Military air vehicle producers use thin, resistive films to enable cutting-edge performance to warfighters, but have been limited by performance and product uniformity, resulting in high scrap rates and parasitic mass. This can be eliminated through use of carbon nanomaterial enhanced thin films, which reduce weight and improve product uniformity by a factor of two. Additionally, this class of nano-enhanced thin films shows potential to provide game-changing performance for future air vehicles.
WHY IT MATTERS
Air vehicles use thin films to provide electrical resistivity where needed, but current materials are limited in performance and uniformity and are supplied by a single source. Without this effort, a sole-source supplier will retain control over high prices and limit purchasing flexibility. Furthermore, the materials’ performance and lack of uniformity translates into high scrap rates and wasted materials and money, which would continue to persist without alternate options. Finally, the current material has some durability issues and provides limited performance at twice the mass of the ASI product, resulting in parasitic mass. ASI materials improve upon robust thin films through the incorporation of advanced carbon nano-scale filaments, which replace traditional macro-scale additives. In order to incorporate the carbon nanofibers, ASI developed a new process for casting thin films, which enables new film species to be produced.
ASI has developed manufacturing technology, qualification methods, and modification techniques for carbon nanofibers. This suite of intellectual property has been applied to engineering properties of thin polymer films for aerospace applications.
“The graphitic nanomaterial reinforced polymeric films produced by Applied Sciences, Inc. offer a lighter weight solution with improved durability, performance, and a significant reduction in cost.”
— Patrick Lake, Vice President at Applied Sciences, Inc.
HOW IT WORKS
Carbon nanofibers (CNF) are in a class of graphitic reinforcement, which can modify physical properties of a composite by reinforcement at the molecular level. Thus, a suite of key physical properties such as strength, modulus, electrical conductivity, thermal conductivity, and coefficient of thermal expansion can be tailored to targeted values with very low loadings of CNF, while minimizing the weight of the resulting composite part. Use of CNF composite materials in aerospace can, therefore, result in improved performance while reducing fuel consumption and maintenance costs, ultimately reducing lifetime operating costs of the component. The advantages of carbon nanofibers were exploited in this project, and through the development of a new film fabrication process, advanced, isotropic thin polymer films have been developed, which provide improved performance, quality, and a reduction in weight. The improvements provided by carbon nanofibers will enable reduction in cost, increased life cycle, and new applications for thin polymer film species on defense platforms.
IMPACT FOR THE FUTURE
Advances in manufacturing technology for CNF thin films represent a critical stepping stone in vertical integration of graphitic nanomaterials into engineered polymers for both defense and commercial applications.
U.S. competition is improved through enhancing the production capability of advanced engineered polymers for defense applications, as well as numerous applications for the lightweighting of commercial vehicle electronics and renewable energy.
Beyond the specific thin film species that is the focus of this effort, the process and ability to incorporate high-aspect ratio carbon nanofibers into film materials will enable the development and commercialization of a wide variety of advanced, nano-enhanced film species.
“ASI’s film materials have the potential for improved performance and increased weight savings compared to the legacy material for current and future defense platforms.”
— Kevin Alt, Program Manager, Advanced Materials and Process Development at Northrop Grumman