TY - JOUR
AU - Mishra, Tarini Prasad
AU - Neto, Rubens Roberto Ingraci
AU - Raj, Rishi
AU - Guillon, Olivier
AU - Bram, Martin
TI - Current-rate flash sintering of gadolinium doped ceria: Microstructure and Defect generation
JO - Acta materialia
VL - 189
SN - 1359-6454
CY - Amsterdam [u.a.]
PB - Elsevier Science
M1 - FZJ-2020-02579
SP - 145 - 153
PY - 2020
AB - In current-rate flash-sintering experiments the current is injected into the specimen from the very start and then increased at a constant rate, while the furnace is held at a constant temperature. The power supply remains under current control. The flash is induced at low current densities which reduces local heating at the electrodes. It leads to a uniform grain size across the entire gage length of the dog-bone specimen. This work pertains to 10 mol.% gadolinium-doped ceria flash sintered at current-rates ranging from 50 mA min−1 to 1000 mA min−1 at a furnace temperature of 680 °C. Full densities are obtained at a current density limit of 200 mA mm–2. Densification is shown to depend only on the instantaneous value of the current density, and not on the current-rate. The grain size, however, is shown to become finer at higher current-rates. A preliminary analysis of the “energy deficit”, that is, the estimated power input corresponding to the temperature as measured with a pyrometer, and the actual power consumption, estimates that huge concentrations of Frenkel defects may be introduced in the flash process.
LB - PUB:(DE-HGF)16
UR - <Go to ISI:>//WOS:000527829900013
DO - DOI:10.1016/j.actamat.2020.02.036
UR - https://juser.fz-juelich.de/record/878010
ER -