Premium
Synthesis and Low‐Temperature Sintering of Gd‐doped CeO 2 Ceramic Materials Obtained by a Coprecipitation Process
Author(s) -
Moure Alberto,
Tartaj Jesus,
Moure Carlos
Publication year - 2009
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2009.03215.x
Subject(s) - sintering , materials science , coprecipitation , microstructure , agglomerate , calcination , isothermal process , scanning electron microscope , ceramic , chemical engineering , metallurgy , oxide , composite material , mineralogy , catalysis , chemistry , physics , engineering , thermodynamics , biochemistry
Well‐dispersed ceria–gadolinia oxide powders were obtained from thoroughly isopropanol‐washed coprecipitated hydroxides and oxalates, followed by a controlled drying at low temperature and calcining at 550°C. The characteristics of the calcined powders and the microstructure of the green compacts were found to be of great importance in the sintering behavior. Green bodies with high agglomerate sizes need higher sintering temperatures for attaining a final density >99% D th , while those having soft agglomerates with lower sizes were almost fully densified at a sintering temperature as low as 1250°C. The densification process was studied by isothermal and constant heating rate dilatometry, and microstructural development by scanning electron microscopy. By controlling the processing variables, it was possible to obtain this low‐temperature, nearly fully dense (better than 99%) sample with a homogeneous microstructure.