SYSTEMS AND THE PROSPECTS FOR CREATING COMPOSITE CERAMIC MATERIALS BASED ON THEM

Abstract

Based on the model of regular solutions and experimental data on quasi-binary sections and individual substances, the liquidus surfaces of SiC–B 4 C–Me d B 2 quasi-ternary eutectic systems (where boride Me d B 2 – CrB 2 , VB 2 , NbB 2 , TaB 2 , TiB 2 , ZrB 2 , HfB 2 , W 2 B 5 ) are built. The paper provides the comparison of theoretical calculations with experimental data and reviews regularities of SiC–B 4 C–Me d B 2 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 Me d B 2 melting point t эвт = f(t пл MedB2 ), the eutectic temperature and MedB2 formation enthalpy : t эвт = f(ΔH f MedB2 ). The type of correlations is close to similar correlations observed earlier in SiC–Me d B 2 and B 4 C–Me d B 2 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.