[en] A complex systematic investigation of the structural state of B³⁺ ions in glasses of zirconium-containing systems has been carried out using electronic microscopy, IR spectroscopy, EPR and Raman scattering. It has been ascertained that the structural state of boron is determined not only by the quantitative content of B₂O₃ and by the ratio B₂O₃/Na₂O+CaO, but also by the structural position of the oxides Al₂O₃ and ZrO₂. Oxides of alkali and alkaline-earth metals provide the polarized oxygen required for building of the tetrahedrons, BO₄. The oxides Al₂O₃ and ZrO₂, on the contrary, compete with boron in using the weakly-bound oxygen, thus increasing the amount of three-coordinated boron

[en] Using the method of quantitative X-ray phase analysis, ceramics on the basis of the Al₂O₃ - TiO₂ system without additions and with additions of ZrO₂ and ZrSiO₄ in amounts from 2.5 to 10 mass % is investigated. The effect of nature and amount of addition on the concentration of Al₂TiO₅, formed in the system, is studied. It is ascertained that the addition of 7.5 mass. % ZrO₂ produces the maximum catalytic effect on tialyte formation, and the effect of ZrSiO₄ is less pronounced. Further increase in the amount of additions decreases the concentration of Al₂TiO₅. Besides, the additions studied improve thermomechanical properties of the ceramics