A unidirectional tape comprising carbon fibers and a fugitive binder is provided,
as well as methods for forming the tape and composite parts using the unidirectional
tape in a resin-transfer molding (RTM) process. A fugitive binder adheres fibers
of the tape. The tape is laid in an RTM mold, and the mold is sealed or vacuum
bagged, then heated. Hot nitrogen gas is pumped through the mold cavity, heating
the carbon fibers to completely pyrolyze the binder. No residue from the binder
remains, as the nitrogen carries gaseous products from the pyrolysis out of the
mold. The mold is cooled to a temperature suitable for resin injection, and resin
is injected into the mold cavity, wetting the fibers of the tape and completely
filling the cavities of the mold. The mold is heated to cause curing of the resin,
then cooled and disassembled for removal of the completed composite component.