ЭКСПЕРИМЕНТАЛЬНЫЕ ИССЛЕДОВАНИЯ И ТЕРМОДИНАМИЧЕСКИЕ РАСЧЕТЫ СТРУКТУРНО-ФАЗОВОГО СОСТАВА В СИСТЕМЕ Ti–Si–C ПРИ ТЕРМООБРАБОТКЕ

Thermodynamic calculations of structural and phase balance in the Ti–Si–C system at 1100–1400 °C was made using the CALPHAD method. The paper demonstrates the calculated phase diagrams of this system. It is found that 100 % of the Ti 3 SiC 2 phase is formed at the stoichiometric relationship of components. Deviations in the carbon or silicon content lead to the formation of titanium carbide, titanium disilicide, or silicon carbide in the system. The phase composition is virtually not affected by the temperature in the examined temperature range. The paper provides comparison of the calculated data with the experimentally determined phase composition of the said system samples after the spark plasma sintering of the mechanoactivated powder. In practice, the process temperature and the duration of high-temperature soak significantly affect the phase composition of the final product due to the limited speed of solid phase reactions during the synthesis of compounds. The resulting samples have a grain size of 1–5 μm and hardness of 4–15 GPa depending on the phase composition.