Improved densification and ionic conductivity in flash-sintered gamma-ray irradiated yttria-stabilized zirconia

Experiments on electric field-assisted pressureless sintering were conducted, with a dilatometer connected to a power supply, in zirconia: 8 mol% yttria polycrystalline ceramics exposed to gamma radiation. During heating to 1000 degrees C, an electric field of 150 V cm(-1) was applied at room temperature up to a sharp thickness shrinkage occurred (flash sintering). It was found that the higher the imparted gamma radiation dose the higher the shrinkage. The shrinkage enhancement and the increase of the total ionic conductivity, when compared to non-irradiated sample, were probably due to the increase of oxygen vacancy concentration after exposure to gamma radiation. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.