STUDY OF THE STRUCTURAL EVOLUTION AND STRENGTHENING OF Li₂TiO₃-BASED CERAMICS DOPED WITH LiNbO₃

Ceramic materials based on lithium metatitanate (Li₂TiO₃) modified with lithium niobate (LiNbO₃) in the concentration range of 0.05–0.25 M were studied. The

Ceramic materials based on lithium metatitanate (Li₂TiO₃) modified with lithium niobate (LiNbO3) in the concentration range of 0.05–0.25 M were studied. The synthesis was carried out by mechanical activation in a planetary mill at grinding speeds of 150…600 rpm with a step of 50 rpm, followed by thermal stabilization at 700 °C for 5 hours. The objective of the work was to determine the relationship between the dopant concentration, the energy of mechanical processing and the structural and mechanical properties of the obtained ceramics.

The phase composition and structural parameters were studied by X-ray diffraction, and the morphological features of the ceramics were studied using scanning electron microscopy. The formation of a two-phase system, including the monoclinic Li₂TiO₃ phase and the rhombohedral LiNbO₃ phase, can be seen. The increase in the dopant content occurs simultaneously with changes in the parameters of the crystal lattice and a decrease in the size of the coherent scattering regions. SEM analysis showed pronounced changes in the morphology of ceramics upon the addition of LiNbO₃, depending on the dopant concentration. Increasing the mechanical activation rate to 600 rpm and increasing the alloying additive concentration to 0.25 M lead to the creation of a fine-grained composite microstructure, where an improvement in the strength characteristics is observed compared to the unalloyed material.

The obtained data show that the combination of changing the LiNbO₃ content and mechanical activation parameters is one of the most effective tools for controlling the phases and strength of lithium-containing ceramic materials, which opens up enormous opportunities for optimization in high-temperature energy applications.

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