Part 2. Structure, mechanical and thermophysical properties of consolidated ceramics based on (Hf,Ta)B2.

Abstract (Hf,Ta)B 2 -based ceramics were produced by hot pressing (HP) and spark plasma sintering of powders obtained by combustion synthesis in Hf-Ta-B system. The dense ceramics possess exceptionally high hardness (60–70 GPa) and Young's modulus (584 GPa). The thermal conductivity is 30.3–52.9 W/m K depending on the phase composition. Plasma torch testing of the single- and two-phase (Hf,Ta)B 2 -based ceramics at 1500–2500 °C demonstrated the formation of a protective multi-layer oxide film with good adhesion to the ceramic, which increases the enthalpy of decomposition of ceramics up to 390 kJ/g. [ABSTRACT FROM AUTHOR]