Commercial Scale Methods for Reclamation and Reuse of Carbon Fiber

One of the biggest challenges associated with fiber-reinforced composites is their recycling, which is exacerbated by the large quantity of rejected parts in aerospace and automotive industry. Various recycling techniques for carbon fiber reinforced polymer (CFRP) composites have been developed; these include: mechanical processes (mainly grinding), thermal recycling, and solvolysis. Thermal recycling in particular has even been implemented at industrial scales, where the matrix is thermally decomposed and evaporated. Thermal recycling is an energy-intensive process; also, fibers degrade at high temperatures during recycling and result in reduced mechanical performance. The recovered fibers and products from resin decomposition are most often systematically characterized and show that they can be reused, but not for high-standard applications. Texas A&M University (TAMU) and University of Washington (UW) faculty have developed a technique to use RF fields to locally heat carbon fillers, specifically carbon fibers (CFs), embedded in polymer matrices. This method provides a quick, low cost route to reclaim CF from CFRP thermoset composites and reintroduce them into aerospace CFRPs or sell them to the automotive, sports, or additive manufacturing industries. For this STTR program, TRI Austin, with support from TAMU and UW, proposes to apply the locally induced RF heating (LIRFH) technology to current Navy aerospace CF composites to recycle the CF and introduce it into defense and commercial applications.