The role of the pore surface area/pore volume ratio in chemical vapor infiltration

Chemical vapor infiltration of a carbon fiber felt with carbon using methane was studied as a test reaction to demonstrate the influence of the pore surface area/pore volume ratio, [A(p)/V-p], on infiltration kinetics as well as structures of the deposited carbon. With progressive infiltration this ratio continuously increases leading to a continuous change in deposition chemistry and kinetics. As a secondary effect carbons of different structures are deposited. All these effects can be exclusively explained with the pore surface area/pore volume ratio, [A(p)/V-p].