INFLUENCE OF YTTRIA DOPANT ON THE STRUCTURE AND PROPERTIES of (ZrO₂)0,91−x(Sc₂O₃)0,09(Y₂O₃)х (x = 0÷0,02) crystals

We have studied the influence of dopant Y₂O₃ oxide (1 and 2 mol.%) on the phase composition, structure and electrical properties of the ZrO₂ — 9 mol.% Sc₂O₃ solid solution. We have shown that stabilization of ZrO₂ jointly with 9 mol.% Sc₂O₃ and 2 mol.% Y₂O₃ allows one to obtain transparent homogeneous crystals with a cubic structure which have a high phase stability. Mechanical grinding of these crystals did not lead to a change in the phase composition of the powders. The powders inherited the original structure of the fluorite crystals. All the test crystals had high microhardness and low fracture toughness. Increasing the concentration of Y₂O₃ in crystals led to the need to reduce maximum loads on the indenter that the sample could withstand without cracking. We have shown that the conductivity varies nonmonotonically with increasing Y₂O₃ concentration in the crystals. An increase in the Y₂O₃ content to 2 mol. % in the composition of the solid electrolyte reduces the conductivity of the crystals in entire temperature range which is caused with a decrease in carrier mobility due to increasing ion radius of the stabilizing ion.

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