Controlled Transformation and Sintering of a Boehmite Sol‐Gel by α‐Alumina Seeding

MASATO KUMAGAI, Gary Lynn Messing

Research output: Contribution to journalArticle

299 Citations (Scopus)

Abstract

The transformation, microstructural development, and densification of an α‐alumina‐seeded boehmite sol‐gel was studied. α‐Alumina particles are shown to act as nuclei for the trans‐ formation of θ‐ to α‐alumina and to result in an increase in the transformation kinetics and lowering of the transformation temperature by as much as 170°C. By increasing the seed concentration (i.e., nucleation frequency), a submicrometer aggregate‐free microstructure develops, rather than the vermicular microstructure that usually characterizes the α‐alumina transformation. As a result, the transformed α‐alumina sinters to full density with a submicrometer grain size at 1200°C. It is believed that seeding may represent a unique method for microstructure control in the many ceramic systems that transform by nucleation and growth.

Original languageEnglish (US)
Pages (from-to)500-505
Number of pages6
JournalJournal of the American Ceramic Society
Volume68
Issue number9
DOIs
StatePublished - Jan 1 1985

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boehmite
Aluminum Oxide
seeding
aluminum oxide
Alumina
Sintering
microstructure
Microstructure
nucleation
Nucleation
sinter
Densification
ceramics
Seed
transform
grain size
seed
kinetics
Kinetics
sintering

All Science Journal Classification (ASJC) codes

  • Ceramics and Composites
  • Materials Chemistry

Cite this

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abstract = "The transformation, microstructural development, and densification of an α‐alumina‐seeded boehmite sol‐gel was studied. α‐Alumina particles are shown to act as nuclei for the trans‐ formation of θ‐ to α‐alumina and to result in an increase in the transformation kinetics and lowering of the transformation temperature by as much as 170°C. By increasing the seed concentration (i.e., nucleation frequency), a submicrometer aggregate‐free microstructure develops, rather than the vermicular microstructure that usually characterizes the α‐alumina transformation. As a result, the transformed α‐alumina sinters to full density with a submicrometer grain size at 1200°C. It is believed that seeding may represent a unique method for microstructure control in the many ceramic systems that transform by nucleation and growth.",
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Controlled Transformation and Sintering of a Boehmite Sol‐Gel by α‐Alumina Seeding. / KUMAGAI, MASATO; Messing, Gary Lynn.

In: Journal of the American Ceramic Society, Vol. 68, No. 9, 01.01.1985, p. 500-505.

Research output: Contribution to journalArticle

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