Sintering and crystallization of off-stoichiometric SrO center dot Al2O3 center dot 2SiO(2) glasses

Authors
Citation
Ym. Sung et S. Kim, Sintering and crystallization of off-stoichiometric SrO center dot Al2O3 center dot 2SiO(2) glasses, J MATER SCI, 35(17), 2000, pp. 4293-4299
Citations number
15
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
JOURNAL OF MATERIALS SCIENCE
ISSN journal
00222461 → ACNP
Volume
35
Issue
17
Year of publication
2000
Pages
4293 - 4299
Database
ISI
SICI code
0022-2461(20000901)35:17<4293:SACOOS>2.0.ZU;2-Y
Abstract
Grass-ceramics with the celsian-corundum binary join composition of 88.8 wt % SrO . Al2O3. 2SiO(2) -11.2 wt% Al2O3, (SA2S-A), were fabricated by pressu reless sintering and investigated for their sintering and crystallization b ehaviors. The (SA2S-A) glass powder showed crystallization peak and melting temperatures of similar to 1059 and 1550 degrees C, respectively and high sintering ability. The (SA2S-A) glass powders containing B2O3, (SA2S-A)B an d those containing B2O3 and TiO2, (SA2S-A)BT showed lowered crystallization peak temperatures of 1033 and 997 degrees C, respectively. By applying Kis siger analyses to the DTA data of the (SA2S-A), (SA2S-A)B and (SA2S-A)BT gl ass powders, the activation energy values for crystallization were determin ed as 488, 370 and 333 kJ/mol, respectively. The Ozawa analyses on the DTA data gave the Avrami parameter values at 1.2, 1.1 and 1.9, respectively for the (SA2S-A), (SA2S-A)B and (SA2S-A)BT glass powders. The x-ray diffractio n (XRD) patterns of the (SA2S-A) glass-ceramics, crystallized at 1100 degre es C for 4 h, showed formation of both the monocelsian and hexacelsian phas es. The (SA2S-A)B and (SA2S-A)BT glass-ceramics crystallized at 1100 degree s C for 1 h, showed formation of the phase-pure monocelsian and did not sho w any evidence of the hexacelsian formation prior to the monocelsian format ion. (C) 2000 Kluwer Academic Publishers.