Pulsed reactive chemical vapor deposition in the C-Ti-Si system from H2/TiCl4/SiCl4

A new route was explored to produce Ti3SiC2-based thin coatings on carbonaceous substrates. This method combines low pressure-pulsed chemical vapor deposition (CVD) and reactive CVD, the gaseous phase being a mixture of SiCl4, TiCl4 and H2. It consists in depositing a pyrocarbon film on the substrate, converting C into SiC (or TiCx) and then converting this carbide into Ti3SiC2. Experiments and thermodynamic calculations were performed and compared. The films were investigated by X-ray diffraction and transmission electron microscopy. Several microstructures consisting of various combinations of Ti3SiC2, C, SiC, TiCx and TiSi2 were obtained.