Liquid‐Phase‐Assisted Transformation of Seeded γ‐Alumina

RICHARD A. SHELLEMAN, Gary Lynn Messing

Research output: Contribution to journalArticle

51 Citations (Scopus)

Abstract

α‐Al2O3‐seeded, boehmite‐derived γ‐Al2O3 was transformed in the presence of V2O5, resulting in a 205°C decrease in the α‐Al2O3 transformation temperature and a 74% reduction in the apparent activation energy for the γ‐ to α‐Al2O3 transformation at temperatures greater than 850°C. These changes are attributed to the lowered energy barrier for nucleation by seeding and the lowered activation energy for material transport through the liquid relative to the unseeded, solid‐state transformation. Growth of the transforming alumina yielded fine‐grained α‐Al2O3 particles which exhibited a highly faceted morphology. It is proposed that the combined control of both nucleation and growth during liquid‐phase‐assisted transformation provides a potentially powerful technique for tailoring powder characteristics in many material systems which undergo nucleation and growth processes.

Original languageEnglish (US)
Pages (from-to)317-322
Number of pages6
JournalJournal of the American Ceramic Society
Volume71
Issue number5
DOIs
StatePublished - Jan 1 1988

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Aluminum Oxide
Nucleation
Alumina
Activation energy
Cloud seeding
Energy barriers
Powders
Temperature
Liquids

All Science Journal Classification (ASJC) codes

  • Ceramics and Composites
  • Materials Chemistry

Cite this

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Liquid‐Phase‐Assisted Transformation of Seeded γ‐Alumina. / SHELLEMAN, RICHARD A.; Messing, Gary Lynn.

In: Journal of the American Ceramic Society, Vol. 71, No. 5, 01.01.1988, p. 317-322.

Research output: Contribution to journalArticle

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