Effect of yttria substitution on structure, optical and mechanical properties of (Gd, Y)2O3–MgO nanocomposite ceramics

A citrate-nitrate combustion method was applied to synthesize fine composite Gd 2-x Y x O 3 -MgO (x = 0, 0.02, 0.2, 0.3, 0.4, 0.6) nanopowders . Y 2 O 3 substitution inhibited Gd 2 O 3 phase transition from cubic structure to monoclinic structure during sintering, thereby stabilizing its cubic structure to room temperature. This approach led to nanocomposite ceramics with a grain size of about 190 nm and increased the transmittance to 85% over the 3–5 μm wavelength range when x = 0.3. However, the addition of Y 2 O 3 weakened the mechanic properties of the nanocomposite ceramics.