Pitch based graphite fabrics and needled punched felts for fuel cell gas diffusion layer substrates and high thermal conductivity reinforced composites

摘要

Disclosed herein is a yarn comprised of a pitch precursor material which has been stretch broken from a first filament count and drawn to a second filament count, with the second filament count being less than the first filament count. Also disclosed is a method of making a graphite fabric comprising the steps of: providing a pitch precursor yarn of a first filament count; stretch breaking and drawing said yarn into a second filament count which is less than the first filament count; forming said yarn into a fabric or felt; and heat treating said fabric or felt to convert the fibers into graphitic fibers. The disclosed pitch precursor yarn, which is stretch broken and formed into a fabric or felt which is heat treated into graphitic fiber media is suitable for fuel cell gas diffusion layer substrates and high thermal conductivity reinforced composites.