In one example, a method includes defibrillating at least one carbon fiber to form a plurality of carbon fiber filaments, melting pitch to form molten pitch, and mixing the plurality of carbon fiber filaments and the molten pitch to form a substantially homogeneous mixture of carbon fiber filaments. In another example, a method includes mixing a plurality of carbon fiber filaments having a length between about 6.35 millimeters and about 50.8 millimeters in molten pitch to form a substantially homogeneous mixture of carbon fiber filaments within the molten pitch, wherein mixing the plurality of carbon fiber filaments does not substantially change an average length of the plurality of carbon fiber filaments.