Title of article :
Preparation and sintering behaviour of a fine grain BaTiO3
powder containing 10 mol% BaGeO3
Author/Authors :
Roberto Ko¨ferstein، نويسنده , , Lothar Ja¨ger، نويسنده , ,
Mandy Zenkner، نويسنده , , Hans-Peter Abicht، نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2008
Abstract :
The formation of solid solutions of the type
[Ba(HOC2H4OH)4][Ti1-xGex(OC2H4O)3] as Ba(Ti1-x/Gex)
O3 precursors and the phase evolution during thermal
decomposition of [Ba(HOC2H4OH)4][Ti0.9Ge0.1(OC2H4O)3]
(1) are described herein. The 1,2-ethanediolato complex 1
decomposes above 589 C to a mixture of BaTiO3 and Ba-
GeO3. A heating rate controlled calcination procedure, up to
730 C, leads to a nm-sized Ba(Ti0.9/Ge0.1)O3 powder (1a)
with a specific surface area of S = 16.9 m2/g, whereas a
constant heating rate calcination at 1,000 C for 2 h yields a
powder (1b) of S = 3.0 m2/g. The shrinkage and sintering
behaviour of the resulting Ba(Ti0.9/Ge0.1)O3 powder compacts
in comparison with nm-sized BaTiO3 powder
compacts (2a) has been investigated. A two-step sintering
procedure of nm-sized Ba(Ti0.9/Ge0.1)O3 compacts (1a)
leads, below 900 C, to ceramic bodies with a relative density
of C90%. Furthermore, the cubic ¡ tetragonal phase
transition temperature has been detected by dilatometry, and
the temperature dependence of the dielectric constant (relative
permittivity) has also been measured
Journal title :
Journal of Materials Science
Journal title :
Journal of Materials Science