A novel sintering method to obtain fully dense gadolinia doped ceria by applying a direct current

A fully dense Ce _0.8Gd _0.2O _1.9 (gadolinia doped ceria, GDC) is obtained by a novel using a sintering technique for several seconds at 545 °C by applying a direct current (DC) electrical field of 70 V cm ^-1. The onset applied field value of this phenomenon is 20 V cm ^-1, and the volume specific power dissipation for the onset of flash sintering is about ∼10 mW mm ^-3. Through contrast with the shrinkage strain of the conventional sintering as well as scanning electron microscopy (SEM) analysis, we conclude that GDC specimens are sintered to fully density under various applied fields. In addition, we demonstrate that the grain size of GDC is decreasing with the increase of applied field and the decrease of sintering temperature. Through calculation, we find that sintering of GDC can be explained by the Joule heating from the applied electrical field.