Field‐assisted heating of Gd‐doped ceria thin film

Abstract

Flash sintering has recently been used to sinter various bulk ceramics under reduced sintering temperatures and sintering time by applying an electric field across the sample. In this work, we have demonstrated field-assisted heating of 10 mol% Gddoped CeO 2 thin films deposited by pulsed laser deposition. Microstructure analysis revealed the elongated grains aligned in the out-of-plane direction which is perpendicular to the direction of electric field. The overall microstructure of the flashheated thin film also contained a matrix of porous and clustered regions, which are distributed throughout the thin film from the anode to cathode electrode regions. The flash-heated thin film showed significantly different conductivity and optical permittivity compared to the as-grown thin films. This demonstration suggests a feasible approach for post-deposition synthesis of thin films using field-assisted heating toward novel morphologies and properties. K E Y W O R D Sconductivity, flash sintering, microstructure, permittivity, thin films

Flash Sintering Research Perspective: A Bibliometric Analysis

“…Moreover, the simplicity of the FS experimental setup is significant, and as mentioned, just a furnace and a power supply are strictly needed, unlike other FAST methodologies that require complex and expensive equipment [1]. Despite its simplicity, FS is an extremely powerful sintering method that can be successfully used for most ceramic materials, from dielectrics (BaTiO 3 [41][42][43][44][45][46][47] or (Bi 0.2 Na 0.2 K 0.2 Ba 0.2 Ca 0.2 )TiO 3 [48]) to ionic (Zirconia, YSZ [2,[49][50][51][52], CeO 2 or doped-CeO 2 [53][54][55][56][57][58]) or electronic (TiO 2 [19,22,[59][60][61][62], BiFeO 3 or substituted-BiFeO 3 [24,27]) conductors. Interestingly, it can be also applied for processing ceramic composites of complex stoichiometry, metastable phases, or materials constituted by volatile species at the temperatures required for their sintering such as YSZ-Al 2 O 3 composites [63][64][65], different types of solid state electrolytes [25,66,67], BiFeO 3 [68,69], or K 0.5 Na 0.5 NbO 3 [26,[70][71][72][73].…”

Flash sintering of additively manufactured 3YSZ gears

“…Flash sintering has also been performed on specimens with simple geometries including cylindrical pellets, 7-10 rectangular bars, 11 and thick or thin films. 12,13 However, these geometries are less commonly used for flash sintering studies due to various challenges, such as their larger cross-sectional areas or complexity in the electrical contact area.…”

“…Currently, the most common sample geometry used for the flash sintering process is dog‐bone shape 1,4‐6 since the electrical contacts can be easily provided to opposing ends of the dogbone and the electrical current can flow uniformly through the thin cross section of the gauge area. Flash sintering has also been performed on specimens with simple geometries including cylindrical pellets, 7‐10 rectangular bars, 11 and thick or thin films 12,13 . However, these geometries are less commonly used for flash sintering studies due to various challenges, such as their larger cross‐sectional areas or complexity in the electrical contact area.…”