Zr0.70[Y1-xNdx]0.30O1.85 as a potential candidate for inert matrix fuel: Structural and thermo-physical property investigations

In order to mimic the loading of americium (Am) and curium (Cm) oxide in yttria stabilized zirconia, Zr0.70 [Y1-xNdx]0.30O1.85 (0.0 ≤ x ≤ 1.0) system was synthesized by solid state route and characterized by X-ray diffraction (XRD) and Raman spectroscopy. The entire system appeared single-phasic fluorite-type by XRD. However, Raman spectroscopy revealed the existence of tetragonal domains for the Nd-rich composition, Zr0.70Nd0.30O1.85 (x = 1.0). Bulk thermal expansion coefficient was found to increase with increasing NdO1.5 content in this series in the temperature range 298-1473 K. The heat capacity of sintered samples was measured by heat flux-type differential scanning calorimeter over the temperature range 313-713 K and it was observed to decrease with increasing Nd3+-content. Thermal conductivity values were determined from measured thermal diffusivity, temperature dependent density and specific heat capacity values. The thermal conductivity of Nd3+ stabilized zirconia was lower than yttria stabilized zirconia.