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Low-Temperature Sintering of High-Strength β-Eucryptite Ceramics with Low Thermal Expansion Using Li2O-GeO2 as a Sintering Additive

2011; Wiley; Volume: 94; Issue: 5 Linguagem: Inglês

10.1111/j.1551-2916.2010.04279.x

1551-2916

Toshio Ogiwara, Yoshimasa Noda, Kazuo Shoji, Osamu Kimura,

Advanced materials and composites

Journal of the American Ceramic SocietyVolume 94, Issue 5 p. 1427-1433 Low-Temperature Sintering of High-Strength β-Eucryptite Ceramics with Low Thermal Expansion Using Li2O–GeO2 as a Sintering Additive Toshio Ogiwara, Corresponding Author Toshio Ogiwara Department of General Education, Ashikaga Institute of Technology, Tochigi 326-8558, Japan *Member, The American Ceramic Society.†Author to whom correspondence should be addressed. e-mail: togi@ashitech.ac.jpSearch for more papers by this authorYoshimasa Noda, Yoshimasa Noda Collaborative Research Center, Ashikaga Institute of Technology, Tochigi 326-8558, JapanSearch for more papers by this authorKazuo Shoji, Kazuo Shoji Department of Electrical and Electronic Engineering, Ashikaga Institute of Technology, Tochigi 326-8558, JapanSearch for more papers by this authorOsamu Kimura, Osamu Kimura Collaborative Research Center, Ashikaga Institute of Technology, Tochigi 326-8558, JapanSearch for more papers by this author Toshio Ogiwara, Corresponding Author Toshio Ogiwara Department of General Education, Ashikaga Institute of Technology, Tochigi 326-8558, Japan *Member, The American Ceramic Society.†Author to whom correspondence should be addressed. e-mail: togi@ashitech.ac.jpSearch for more papers by this authorYoshimasa Noda, Yoshimasa Noda Collaborative Research Center, Ashikaga Institute of Technology, Tochigi 326-8558, JapanSearch for more papers by this authorKazuo Shoji, Kazuo Shoji Department of Electrical and Electronic Engineering, Ashikaga Institute of Technology, Tochigi 326-8558, JapanSearch for more papers by this authorOsamu Kimura, Osamu Kimura Collaborative Research Center, Ashikaga Institute of Technology, Tochigi 326-8558, JapanSearch for more papers by this author First published: 18 January 2011 https://doi.org/10.1111/j.1551-2916.2010.04279.xCitations: 20 I. Reimanis—contributing editor Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Abstract Low-temperature sintering of high-strength β-eucryptite ceramics with low positive coefficient of thermal expansion (CTE) was attained using Li2O–GeO2 sintering additive. High-purity β-eucryptite could be synthesized using high-purity and fine amorphous silica, α-alumina, and lithium carbonate powder mixture at 950°C via the solid-state reaction route. Accordingly, the mixture was calcined at 900°C, pulverized, compacted, and sintered at 1020°C for 2 h with the sintering additive. The sintering temperature could be lowered by about 300°C, compared with the sintering temperature previously reported. The relative density of the sintered sample reached 99% of true density. Its flexural strength and indentation fracture toughness were 214 MPa and 2.5 MPa·m1/2, respectively. Its CTE (from room temperature to 800°C) was 1.2 × 10–6/K. Its dielectric constant was 5.5 with a loss tangent of 7.5 × 10–3. However, prolonged sintering time resulted in large negative CTE and mechanical weakness in the sintered samples. Microcracks were introduced with prolonged sintering time, which caused their large negative CTE with mechanical weakness. Citing Literature Volume94, Issue5May 2011Pages 1427-1433 RelatedInformation