Active filler controlled polymer pyrolysis – A promising route for the fabrication of advanced ceramics

A novel polyborosiloxane (BoSiVi) containing methyl and vinyl groups with Titanium Silicide (TiSi2) filler was employed for the preparation of silicon and titanium containing ceramic phases. Ceramic phase evolution was studied from the above mentioned preceramic system at 900, 1200, 1500, 1800 and 2000 °C respectively under argon atmosphere. Reactive nature of TiSi2 with pyrolytic by-products of BoSiVi led to the formation of different ceramic phases at different firing temperatures. XRD analysis confirmed the evolution of carbide (TiC, TiB, SiC etc.) and oxide (TiOC, SiO2 etc.) ceramic phases in the temperature regime of 900 °C to 1500 °C. FESEM-EDX analysis of the ceramic phases, heat treated at 1500 °C, proved the formation of Si-Ti-O-C ceramic nano-fibers by Vapor-Liquid-Solid (VLS) method. BoSiVi+TiSi2 system heat treated at 1800 °C and 2000 °C exhibited the evolution of pure non-oxide ceramic phases along with Ti3SiC2 MAX phase.