Synthesis of TiB2/TiC/Al2O3 and ZrB2/ZrC/Al2O3 Composites by Low-Exotherm Thermitic Combustion with PTFE Activation

TiB2–TiC–Al2O3 and ZrB2–ZrC–Al2O3 composites were produced via PTFE (polytetrafluoroethene)-activated combustion synthesis involving low-exotherm thermites. The reactant stoichiometries 3TiO2 + 4Al 0.5B4C (1 ? x)C xCPTFE 3ZrO2 y)C yCPTFE. played a dual role in promoting the reaction carburizing reduced Ti Zr. threshold amount of for TiO2/Al-based was 2 wt% (i.e., x = 0.15) ZrO2/Al-based 3 y 0.25). increase increased front velocity temperature. more exothermic than exhibited faster lower activation energy. composite with minimum at 0.15. formation required 0.5 to improve reduction ZrO2. Both triplex displayed mixed microstructures consisting short-rod borides, fine spherical carbides, Al2O3 agglomerates.