SiC–B4C–MedB2 systems and the prospects for creating composite ceramic materials based on them (original) (raw)

Based on the model of regular solutions and experimental data on quasi-binary sections and individual substances, the liquidus surfaces of SiC–B4C–MedB2 quasi-ternary eutectic systems (where boride MedB2 – CrB2, VB2, NbB2, TaB2, TiB2, ZrB2, HfB2, W2B5) are built. The paper provides the comparison of theoretical calculations with experimental data and reviews regularities of SiC– B4C–MedB2 phase diagrams. It is found that there is a regular decrease in diboride concentration in the ternary eutectics with the increase in its melting point. Correlations are established between the eutectic temperature and MedB2 melting point teut = f(tm MedB2), the eutectic temperature and MedB2 formation enthalpy teut = f(ΔHf MedB2). The type of correlations is close to similar correlations observed earlier in SiC–MedB2 and B4C–MedB2 boundary quasi-binary systems. The structure and parameter analysis of the reviewed systems allows for the conclusion on the prospects of developing a wide range of engineering and functional ceramic materials and coatings based on these systems and obtained by pressureless sintering, as well as heating and consolidation pulse methods.