Synthesis and Study of Composite Materials in the ZrO2(Y2O3)–MgAl2O4 System

Powders–precursors of a tetragonal solid solution based on partially stabilized zirconium dioxide (t-ZrO2) and aluminum-magnesium spinel (MgAl2O4) are synthesized using the method of the cocrystallization of solutions of nitrate salts from which nanocrystalline (<100 nm) composite materials are fabricated at 1400°C in the ZrO2(Y2O3)–MgAl2O4 system with an open porosity of 3%. The structure, physical–mechanical properties, and thermal stability of the nanocomposites are investigated. It is established that the introduction of MgAl2O4 into the matrix of the solid t-ZrO2 solution increases the thermal resistance of the ceramics under the thermal cycling conditions (20–1000°С). The effect of thermal cycling on the phase composition, hardness, and bending strength of the ceramics in the ZrO2(Y2O3)–MgAl2O4 system is investigated.