Geoscience Reference
In-Depth Information
Table 10.8 Density, Grain Size, and Dielectric Properties of the Sintered BaTiO
3
Samples
[368]
Grain Size
a
(
μ
m)
Density
b
(g/cm)
k
0
(30
C)
Type of
Sintering
Sintering
T
(
C)
tan
δ
(30
C)
T
o
(
C)
C
(
3
10
5
K)
Conventional 1250
2814
0.038
B
4
5.61 (93)
108
1.8
1300
2663
0.039
B
20
5.63 (93)
109
1.9
1350
2558
0.037
28
5.59 (94)
112
2.0
B
Fast—5 min
1250
3676
0.020
1
5.53 (92)
84
2.1
B
1300
3274
0.020
B
2
5.65 (94)
97
1.7
1350
2892
0.009
B
4
5.71 (95)
110
1.8
Fast—
15 min
1250
2947
0.009
B
6
5.76 (96)
111
1.9
1300
2721
0.006
B
12
5.89 (98)
111
2.0
a
Average grain size determined by taking the mean diagonal values of about 30 grains.
b
Values in parentheses are the percentage relative densities compared to the theoretical density.
12,000
0.4
10,000
0.3
8000
6000
0.2
4000
0.1
2000
0
0.0
30
50
70
90 110
Temperature (
°
C)
130
150
170
190
Figure 10.82 Dielectric properties (k
0
and tan
δ
) of BaTiO
3
[368]
.
synthesis
[374,375]
, organometallic synthesis
[376,377]
, and preparation of interca-
lation compounds
[378]
where organic molecules have been intercalated into inor-
ganic phases. Hydrated inorganic zeolites and other molecular sieves have been
synthesized rapidly, using microwaves
[379,380]
.
Komarrneni and coworkers, however, were the first to show the rapid synthesis of
anhydrous ceramic oxides
[38,381,382]
, hydroxylated phases
[383,384]
, metal pow-
ders
[383,385]
, and metal-intercalated clays
[386,387]
. Also, the rapid synthesis of
some inorganic phases, such as ZrO
2
and Fe
2
O
3
,havebeenreported
[388
390]
.In
addition to all the above-quoted inorganic phases, microwave-hydrothermal proces-
sing is useful in synthesizing novel phases
[383,391]
. Komarneni et al.
[392]
prepared
