SPECTROSCOPIC CHARACTERIZATION OF CVD TI COATING ON SIC-COATED BORON FIBERS

Auger electron and X-ray photoelectron spectroscopies were employed to investigate the fiber-matrix interface produced by the chemical vapor deposition of titanium on SICABO and BORSIC fibers at 1040-degrees-C. Chemical state information about the titanium coating and the Ti/SiC interface was obtained. The chemical nature of the coating was observed through the behavior of the Si 2p, C 1s, and Ti 2p photoelectron core levels and their corresponding Si LVV, C KLL, Ti LMM, and Ti LMV Auger electron spectra. Sputter-depth profiling was employed to complete the characterization of the material formed by interfacial reaction. The Ti was found to react with the BORSIC fiber, forming large amounts of titanium silicides and titanium carbide, whereas only small amounts of titanium carbide and titanium silicides were formed with the SICABO fiber. Sputter-depth profiling reveals that growth of the titanium silicides and carbide takes place over considerable depth into the BORSIC fiber. The reaction zone in titanium-coated SICABO fiber was not as broad.