TY  - JOUR
AU  - Mishra, Tarini Prasad
AU  - Laptev, Alexander
AU  - Ziegner, Mirko
AU  - Sistla, Sree Koundinya
AU  - Kaletsch, Anke
AU  - Broeckmann, Christoph
AU  - Guillon, Olivier
AU  - Bram, Martin
TI  - Field-Assisted Sintering/Spark Plasma Sintering of Gadolinium-Doped Ceria with Controlled Re-Oxidation for Crack Prevention
JO  - Materials
VL  - 13
IS  - 14
SN  - 1996-1944
CY  - Basel
PB  - MDPI
M1  - FZJ-2020-02580
SP  - 3184 -
PY  - 2020
N1  - Open Access Journal
AB  - Gadolinium-Doped Ceria (GDC) is a prospective material for application in electrochemical devices. Free sintering in air of GDC powder usually requires temperatures in the range of 1400 to 1600 °C and dwell time of several hours. Recently, it was demonstrated that sintering temperature can be significantly decreased, when sintering was performed in reducing atmosphere. Following re-oxidation at elevated temperatures was found to be a helpful measure to avoid sample failure. Sintering temperature and dwell time can be also decreased by use of Spark Plasma Sintering, also known as Field-Assisted Sintering Technique (FAST/SPS). In the present work, we combined for the first time the advantages of FAST/SPS technology and re-oxidation for sintering of GDC parts. However, GDC samples sintered by FAST/SPS were highly sensitive to fragmentation. Therefore, we investigated the factors responsible for this effect. Based on understanding of these factors, a special tool was designed enabling pressureless FAST/SPS sintering in controlled atmosphere. For proof of concept, a commercial GDC powder was sintered in this tool in reducing atmosphere (Ar-2.9%H2), followed by re-oxidation. The fragmentation of GDC samples was avoided and the number of micro-cracks was reduced to a minimum. Prospects of GDC sintering by FAST/SPS were discussed.
LB  - PUB:(DE-HGF)16
C6  - pmid:32708746
UR  - <Go to ISI:>//WOS:000554233400001
DO  - DOI:10.3390/ma13143184
UR  - https://juser.fz-juelich.de/record/878011
ER  -