TiC was deposited onto several steel substrates by the chemical vapor deposition technique from $TiCl_4-CH_4-H_2$ gas mixtures in the horizontal resistance furnace. Deposition rates and morphologies of the coatings were investigated with the carbon contents. Deposition thickness increased linearly with the deposition time in the presence of $CH_4$ gas. The slope of the deposition thickness vs deposition time becomes steeper as carbon contents increase. The carbon of the TiC layer originates from the $CH_4$ gas as well as from the steel substrate itself. The contribution of carbon from the steel substrate dominates when the carbon activity in the steel is relatively high. Therefore the CVD experiments on various iron-carbon substrates without and with carbon supply in the gas phase were investigated. The influence of carbon contents and Cr contents on TiC layer thickness, microhardness, wear resistance was not investigated very well.
The various carbide layers of TiC coating by EDAX and X-ray diffractometer were investigated. The relation of wear resistance and the texture coefficient with the carbon contents was investigated through the experiments. The preferred orientation of layer growth about carbon contents, Cr contents was determined. The deposition mechanisms are divided into a mass transfer controlled and surface controlled reaction. The activation energy of the reactions is determined for different Cr contents.
It is shown that deposition rate is dependent on Cr contents but preferred orientation of TiC coating growth is not dependent.
