Formation of C/SiC multilayer coating on Si–Ti–C–O fiber

C/SiC multilayer coatings thinner than a micron were deposited on Si–Ti–C–O fibers by repeated alternation of argon and hydrogen as dilute gases. Films were formed by chemical vapor infiltration on graphite substrates coated with SiC, using tetrachlorosilane (SiCl4) and methane (CH4) as the source and pure argon, hydrogen, or a mixture of the two as the dilute gas, in order to investigate the effect of the dilute gas on the filmʹs properties and deposition behavior. When the dilute gas was pure argon, pyrolytic carbon was formed, but when hydrogen was present in the dilute gas SiC tended to be formed.