Stress Graphitization Behavior of c/c Composites Fabricated from Milled Short Pitch-Based Carbon Fibers and their Electrical Properties

This study focuses on the possibility of applying recycled carbon fiber (CF) as a high electric conductivity material for use in CF-reinforced carbon composites, i.e., the so-called c/c composites, in the future. For this application, discontinuous CF- reinforced furan resin films were molded, and discontinuous CF-reinforced carbon (D-c/c) films were fabricated through carbonization and graphitization, respectively (D-c/c-C:after carbonization at 1500 ̊C, D-c/c-G: after graphitization at 3000 ̊C. The apparent density of the matrix in D-c/c-C increased owing to stress graphitization, leading to this densification of the matrix after the graphitization process. Stress graphitization was proved by varying the shrinkage of the matrix with the amount of hardener added. The electrical conductivity of D-c/c-c-G, where graphitization progressed the most,reached 1.80 × 105 S/m. We revealed the possibility of using D-c/c-G as a high-conductivity material for future applications.