Yttria thermal expansion coefficients

XRD at different temperatures can be used to study phase transitions between different crystallographic forms of a material (e.g., tetragonal vs. monoclinic forms of yttria-stabihzed zirconia). This approach can be used to measure thermal expansion coefficients and to study crystalline-to-amorphous transitions in materials. 

The Poisson ratio of yttria is 0.31, and the elastic modulus 170 G Pa. The material has a relatively high thermal expansion coefficient (9.1 x 10 K ), which is comparable to that of polycrystalline alumina, and a high thermal conductivity (14 W mK ), which is twice that of the other solid-state laser host material, Y3AI5O12 (YAG). Yttria has also a very high electrical resistivity (lO cm), is refractory by... 

At even higher temperatures in the range of 800-900 °C, ionic conduction can also be observed in solid oxides. Certain doped metal oxides become conductors hence, they can be utilized as electrolytes in the solid oxide fuel cell (SOFC). The most common oxide used is yttria-stabilized cubic zirconia (Zr02), called YSZ, with a doping level of 8% Y2O3. This material is a ceramic the thermal expansion coefficient of its thin layers has to be matched with the other fuel cell components. 

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