Measurement of dielectric properties of rare earth oxides by resonance cavity perturbation method

The dielectric properties and thermostable characteristics of 15 rare earth oxides are systematically investigated in microwave fields. Results indicate that the Pr6O11 of the light and Tb4O7 of the heavy rare earth oxides show excellent responsiveness to microwaves, both start to surge after 500 °C, with dielectric constant values of 10.814 and 10.157 (F/M) at 800 °C, respectively, meaning that it takes only 8.8 min for Pr6O11 and Tb4O7 to be heated from 150 to 800 °C. The dielectric properties of rare earth oxides are related to their thermostable characteristics, mainly affected by crystal transformation. Moreover, the Ln2O3-type rare earth oxides have no crystal transformation within the range of microwave heating to 800 °C, and the changes in dielectric properties and heating curve are attributed to lattice distortion of the particles. This work provides guidance for applications of microwave technology to the rare earth oxides.