Variation of grain boundary dihedral angles caused by voltage-to-current-based flash treatment in fully stabilized yttria-doped zirconia polycrystals

Abstract

The flash sintering method has garnered attention for its ability to significantly accelerate the densification rate of ceramic green compact through the generation of an electric power spike under an electric field exceeding a defined threshold. In order to amass foundational knowledge about the phenomenon that results from an electric field during flash sintering via a voltage-to-current protocol, the dihedral angles of grain boundaries were surveyed in flash-treated pre-sintered fully stabilized zirconia polycrystal. The flash treatment resulted in a reduction of the grain boundary dihedral angle for grain boundaries that are approximately perpendicular to the direction of the electric field. The reduction in the dihedral angle is possibly attributed to a reduction in surface energy which can be observed through the formation of sinuous pores during flash sintering.