The purpose of the present paper is to study the influence of glass composition on the thermal stability in the SiO2B2O3BaO system, and three glasses were consequently investigated. Although Glass A has a coefficient of thermal expansion (CTE) that shows the best match with those of anode and electrolyte materials of solid oxide fuel cells (SOFCs), the thermal stability of Glass A is quite poor, where after being heat treated at 800°C for only 8h, the CTE of the glass increased more than 24%. The change of the CTE value was mainly attributed to the fast crystallization that formed high CTE value phases such as BaB2O4 and Ba2Si3O8. In order to improve the thermal stability, BaO in Glass A was replaced by B2O3 (Glass B) and SiO2 (Glass C). It was found that the decrease in the BaO content improved the thermal stability of the resultant glasses. Glass B showed less than 8% change of the CTE during annealing time at 800°C, while Glass C exhibited superior long-term thermal stability, where the change of the CTE was within the equipment detection limit after being heat treated for 300h at 800°C. The good thermal stability of Glass C was believed to be due to the formation of a more compact glass network after the substitution as compared with that of Glass A. The good thermal stability makes Glass C attractive to be used as the sealing material for SOFC applications.

1.
Yang
,
Z. G.
,
Stevenson
,
J. W.
, and
Meinhardt
,
K. D.
, 2003, “
Chemical Interactions of Barium-Calcium-Aluminosilicate-Based Sealing Glasses With Oxidation Resistant Alloys
,”
Solid State Ionics
0167-2738,
160
, pp.
213
225
.
2.
Weil
,
K. S.
, 2006, “
The State-of-the-Art in Sealing Technology for Solid Oxide Fuel Cells
,”
JOM
1047-4838,
58
(
8
), pp.
37
44
.
3.
Sohn
,
S. B.
,
Choi
,
S. Y.
,
Kim
,
G. H.
,
Song
,
H. S.
, and
Kim
,
G. D.
, 2004, “
Suitable Glass-Ceramic Sealant for Planar Solid-Oxide Fuel Cells
,”
J. Am. Ceram. Soc.
0002-7820,
87
(
2
), pp.
254
260
.
4.
Ley
,
K. L.
,
Krumpelt
,
M.
,
Kumar
,
R.
,
Meiser
,
J. H.
, and
Bloom
,
I.
, 1996, “
Glass-Ceramic Sealants for Solid Oxide Fuel Cells: Part I. Physical Properties
,”
J. Mater. Res.
0884-2914,
11
(
6
), pp.
1489
1493
.
5.
Weil
,
K. S.
,
Coyle
,
C. A.
,
Hardy
,
J. S.
,
Kim
,
J. Y.
, and
Xia
,
G. G.
, 2004, “
Alternative Planar SOFC Sealing Concepts
,”
Fuel Cells Bull.
1464-2859,
5
, pp.
11
16
.
6.
Brochu
,
M.
,
Gauntt
,
B. D.
,
Shah
,
R.
, and
Loehman
,
R. E.
, 2006, “
Comparison Between Micrometer- and Nano-Scale Glass Compositions for Sealing Solid Oxide Fuel Cells
,”
J. Am. Ceram. Soc.
0002-7820,
89
(
3
), pp.
810
816
.
7.
Eichler
,
K.
,
Solow
,
G.
,
Otschik
,
P.
, and
Schaffrath
,
W.
, 1999, “
BAS (BaO⋅Al2O3⋅SiO2)-Glasses for High Temperature Applications
,”
J. Eur. Ceram. Soc.
0955-2219,
19
, pp.
1101
1104
.
8.
Bansal
,
N. P.
, and
Gamble
,
E. A.
, 2005, “
Crystallization Kinetics of a Solid Oxide Fuel Cell Seal Glass by Differential Thermal Analysis
,”
J. Power Sources
0378-7753,
147
(
1–2
), pp.
107
115
.
9.
Weil
,
K. S.
,
Deibler
,
J. E.
,
Hardy
,
J. S.
,
Kim
,
D. S.
,
Xia
,
G. G.
,
Chick
,
L. A.
, and
Coyle
,
C. A.
, 2004, “
Rupture Testing as a Tool for Developing Planar Solid Oxide Fuel Cell Seals
,”
J. Mater. Eng. Perform.
1059-9495,
13
, pp.
316
326
.
10.
Brochu
,
M.
,
Gauntt
,
B. D.
,
Shah
,
R.
,
Miyake
,
G.
, and
Loehman
,
R. E.
, 2006, “
Comparison Between Barium and Strontium-Glass Composites for SOFCs
,”
J. Eur. Ceram. Soc.
0955-2219,
26
(
5
), pp.
3307
3313
.
11.
Reis
,
S. T.
, and
Brow
,
R. K.
, 2006, “
Designing Sealing Glasses for Solid Oxide Fuel Cells
,”
J. Mater. Eng. Perform.
1059-9495,
15
, pp.
410
413
.
12.
Zhu
,
Q. S.
,
Peng
,
L.
, and
Zhang
,
T.
, 2007,
Fuel Cell Electronics Packing
,
Springer
,
New York
, Chap. 2, p.
41
.
13.
Zhu
,
Q. S.
,
Peng
,
L.
,
Huang
,
W. L.
, and
Xie
,
Z. H.
, 2007, “
Ultra Stable Sealing Glass for Intermediate Temperature Solid Oxide Fuel Cell Applications
,”
Key Eng. Mater.
1013-9826,
336–338
, pp.
481
485
.
14.
Larsen
,
P. H.
, and
James
,
P. F.
, 1998, “
Chemical Stability of MgO∕CaO∕Cr2O3–Al2O3–B2O3-Phosphate Glasses in Solid Oxide Fuel Cell Environment
,”
J. Mater. Sci.
0022-2461,
33
, pp.
2499
2507
.
15.
Liu
,
J. F.
,
He
,
X. M.
,
Zhou
,
G. Q.
,
Zhou
,
S. M.
,
Zhao
,
G. J.
, and
Li
,
S. Z.
, 2004, “
The Study on Properties of Sr2+-Doped α-BBO Crystal
,”
J. Cryst. Growth
0022-0248,
260
, pp.
486
489
.
You do not currently have access to this content.