A Novel Precursor for the Synthesis of Mixed Non-oxide Ultra High Temperature Ceramics

Polymer-derived ceramics have gained importance due to ease of processability, less processing time and flexibility in tailoring the composition of ceramics by altering the monomer ratios in the polymer. In the present work, a preceramic oligomer containing both zirconium and titanium, viz., Zirconotitanoborosiloxane was synthesized by non-aqueous sol-gel process. Oligomer was characterized by GPC, spectral and thermal techniques. Ceramics formed at 1500 degrees C reveal the formation of Zr and Ti based UHTCs along with some oxides. To study the feasibility of using Zirconotitanoborosiloxane oligomer as precursor for mixed non-oxide ceramics, carbothermic and borothermic reductions were carried out by blending the precursor with phenolic resin as source of carbon and elemental boron as source of boron. XRD study confirms the formation of mixed non-oxide UHTC system containing Zr, Ti, B, Si and C. SEM-EDS analysis revealed the micro-structure of the ceramics and elemental composition.