Porous carbon-carbon preforms, 10.8 cm o.d.×4.4 cm i.d.×3.0 cm thick have been densified in a one-cycle, 26 h process. The disks are heated by induction, creating an inside-out thermal gradient, and are exposed to cyclopentane vapor in a water-cooled vacuum chamber. Rough-laminar carbon microstructure is obtained; a compressive strength of 268 MPa is measured at 1.79 g/ cm3 density. The densification rate is monitored in real time. The precursor utilization efficiency is 20%-30%. Our patented process can be applied to other materials, has significant scale-up potential and is economically competitive.© 1995 American Institute of Physics.
