Phase diagram of the Tb3Sc2Al3O12–TbScO3 system

DOI: 10.62564/M4-SL1252

Serhii Lakyza, Monica Tomchzyk, Jaroslaw Korol, Dorota-Anna Pawlak

ENSEMBLE3, Centre of Excellence, Poland


Eutectics present the unusual characteristic of being at the same time a monolith and a multiphase material. They have the potential for optical, electronic and magnetic applications. Their properties can be divided into two categories: additive properties and product properties. The additive properties depend on volume fraction and spatial distribution of the phases, while the product properties depend on interaction between the phases and depend on periodicity and the size of the phases. The Tb3Sc2Al3O12–TbScO3 (TSAG-TSP) eutectic is interesting optically active material in which both radiative and measured lifetimes of 5D4 manifold of Tb3+ ions are longer than in bulk TSAG and TSP crystals. These eutectic materials have a high potential for photonic applications. The authors [1] grew TSAG single crystals by micro-pulling down method and found the formation of areas of binary eutectic TSAG-TSP at the edge of TSAG single crystal. The reason was the composition deviation during the growing process. So the quasibinary section TSAG-TSP was stablished in the system Tb2O3–Sc2O3–Al2O3. Then the directional solidification of TSAG-TSP eutectic was performed [2], but the coordinates of this eutectic was not established and bulk material with primary TbScO3 crystals was obtained. At the present time we have no information about phase diagram of this system, so the construction of it is the purpose of given investigation. The bulk directionally solidified µPD crystal was analyzed by DTA, SEM+EDS methods and coordinates of TSAG-TSP eutectic was established (1805 °C, 25 mol.% TbScO3). TbScO3-based solubility area does not exceed ~1 mol.%. TSAG-based solubility was not determined. Phase diagram of this system is shown in Fig. 1, microstructures – in Fig. 2.

Keywords
Eutectic, phase diagram, Tb3Sc2Al3O12, TbScO3

Acknowledgments
Not provided

References
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