LEAPS-MPS: Exploring Centrifugal Jet Spinning of Ultra-High-Temperature Ceramic Nanofibers

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This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).NON-TECHNICAL DESCRIPTION: This research project consists of a novel method to fabricate micro- and nano-sized ceramic fibers that can withstand several thousand degrees Celsius without melting. A metal salt and a polymer are dissolved to make a viscous solution that is subsequently spun into fibers. The fibers are then heat treated to react the metal with the carbon in the polymer and form the ultra-high-temperature ceramic fiber. The effects of high temperatures and oxygen in the atmosphere on the fibers’ microstructure are also studied. This research makes it possible to fabricate, in large quantities and at low temperature, ceramic nanofiber mats of compounds not available in fiber form. These ultra-high temperature ceramic fiber mats can contribute to thermal protection systems that allow aircraft, missiles, and rockets to travel faster and for a longer period at hypersonic speed. Two undergraduate students and two graduate students from a minority-serving institution are obtaining laboratory experience in ceramic manufacturing and testing. Another 8 to 16 undergraduate students are engaged in designing, fabricating, and testing equipment for ceramic materials characterization. Graduates typically find employment in the high-tech industry or further pursue graduate degrees.TECHNICAL DETAILS: Several synthesis methods exist for the fabrication of transition metal carbide nanocrystalline nanoparticles, nanorods, nano-powders, and nanowires; however, it is still a great challenge to fabricate long and continuous ultra-high-temperature transition metal carbide nanofibers using scalable techniques for mass production. In this project, novel transition-metal carbide nanofibers are fabricated by the carbothermal reduction of polymer precursor nanofibers manufactured by centrifugal jet spinning. Centrifugal jet spinning uses centrifugal forces to produce fibers from solutions at speeds and costs similar to melt-blown and glass fiber methods and is used in this project to leverage the energy-efficient polymer precursor synthesis method with the added benefit of being easily scalable for mass production. The oxidation behavior of the fibers is also investigated. The knowledge obtained from this project can be useful to fabricate other ceramic fibers in large quantities. In addition, this research provides opportunities for undergraduate and graduate students of underrepresented groups to obtain hands-on experience in materials science and engineering.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.