Synthesis, characterization and microstructure of tantalum carbide-based ceramics by liquid polymeric precursor method

A novel soluble precursor for tantalum carbide was prepared by blending allyl-functional novolac resin (AN) with a tantalum-containing polymer named polytantaloxanesal, which was synthesized by hydrolysis and polycondensation of an acetylacetone coordinated monomer containing tantalum. Tantalum carbide (TaC) ceramics were formed by pyrolysis of the precursors at 1400 °C in argon. The thermal behavior, phase composition and microstructure of the ceramics were investigated. The carbothermal reduction process started at 900 °C, and fully completed at 1400 °C. The mean crystallite size of the precursor-derived TaC ceramics was less than 30 nm and Ta and C elements were homogeneously distributed in the ceramic samples.