USE OF STABILIZING ADDITIVES FOR TARGETED MODIFICATION AND HARDENING OF Nd2Zr2O7 CERAMICS

This paper presents the results of experimental work related to the preparation of Nd₂Zr₂O₇ ceramics stabilized by Y₂O₃, the choice of which is due to the great prospects for their use as materials for inert matrices of dispersed nuclear fuel. During the conducted experiments aimed at determining the effectiveness of the influence of stabilizing additives in the form of Y₂O₃ on the change of structural and strength parameters of Nd₂Zr₂O₇ ceramics it was found that the increase in the concentration of stabilizing additives above 0.1 M leads to the formation of inclusions in the structure in the form of Y₂Zr₂O₇ grains, the formation of which is associated with the effects of polymorphic transformations in zirconium dioxide during high-temperature annealing. It was determined that the substitution of zirconium cations by yttrium cations leads to an increase in the concentration of oxygen vacancies in ceramics composition, the change in the concentration of which is also associated with phase transformations in the structure, arising at high concentrations of stabilizing dopant. At the same time, the optimum concentration of stabilizing additives is the concentration of 0.15 M, at which the ratio of structural and strength parameters has optimum values, determining their potential use as materials of inert matrices of dispersed nuclear fuel with high strength characteristics.

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