Densification of a 2D carbon fiber preform by isothermal, isobaric CVI: Kinetics and carbon microstructure

摘要

Chemical vapor infiltration of a 2D carbon fiber preform with a 0/0/90/90 deg fiber architecture and a fiber volume fraction of 22.5 percent was investigated as a function of methane pressure at various temperatures as well as a function of infiltration time at constant pressure. Inside-outside densification was obtained at the most attractive temperature of 1095 deg C up to 29 kPa resulting in a maximum bulk density of 1.84 g cm~(-3) and a matrix density of 2.17 g cm~(-3), which corresponds to high-textured carbon. Texture formation can be perfectly explained with the earlier proposed particle-filler model. Studies at increasing infiltration times suggest a recrystallization of carbon deposited in the early stages of the infiltration.