An extended interpretation of chemical vapor infiltration of carbon

Abstract
Chemical vapor infiltration of carbon with methane as carbon source was studied considering complex deposition chemistry and kinetics. Numerical simulations of the infiltration of capillaries showed deposition profiles increasing from the mouth to the depth of the capillary provided that residence time and thus predecomposition of methane outside of the capillary are sufficiently short or small, respectively. The increase of the deposition profile is significantly enhanced with increasing complexity of deposition chemistry (length of the reaction sequence of gas phase reactions), increasing depth of the capillary and increasing methane pressure. The results were experimentally confirmed by corresponding infiltration experiments. As compared to these results, decreasing deposition profiles are only known from literature.