STUDY OF STRUCTURAL DAMAGE MECHANISMS IN STABILIZED CERAMICS BASED ON ZIRCONATES UNDER HIGH-TEMPERATURE IRRADIATION WITH HEAVY IONS

The paper presents a comprehensive description of the results of experimental work related to the study of the mechanisms of radiation damage accumulation during the irradiation with heavy Xe + ions of the studied samples of Nd 2 Zr 2 O 7 ceramics in the unstabilized state, and stabilized with 0.15 M MgO and Y 2 O 3 , the adding of which according to the data of X-ray phase analysis leads to the formation of impurity inclusions in the structure in the form of MgO and Y 2 Zr 2 O 7 grains, which create a buffer protective layer in the intergranular space, the presence of which leads to an increase in resistance to radiation-induced processes of unstrengthening and reduction of thermophysical parameters. In the course of determining the dependences of changes in strain distortion resulting from the accumulation of structural stresses in the crystal structure and amorphization, which was determined on the basis of changes in the intensity of diffraction maxima, the equally probable influence of both processes at high-dose irradiation on the degradation of the near-surface damaged layer was determined, as well as the positive influence of stabilizing components on the inhibition of amorphization and strain distortion at high-dose irradiation. The analysis of changes in strength and thermophysical parameters of Nd 2 Zr 2 O 7 ceramics subjected to irradiation by heavy ions has shown that the addition of stabilizing additives in the form of MgO and Y 2 O 3 to ceramics composition leads to increased resistance to radiation-induced processes of de-strengthening and thermal conductivity degradation caused by the accumulation of structural deformation distortions and metastable inclusions in the damaged layer.