Microstructural development of Nd, Gd and Yb-Doped α'/β' sialons

Research output: Contribution to journalArticle

Abstract

Rare-earth doped sialons have been studied to compare the effects of different stabilising cations (Nd, Gd and Yb) on the phase content and microstructures of cc'/β' composites, and on the degree of α'→β' transformation following heat-treatment of the samples at 1450°C. Heat-treatment of the Gd and Yb sialons resulted in crystallisation of the residual glassy phase into Gd-aluminate or Yb-garnet, respectively, with very little transformation of a' to β' taking place. In contrast, heat-treatment of the Nd sialons readily promoted the transformation of a' to β', with a corresponding evolution of Nd-Aluminate or Nd-Wollastonite. In addition, β-Si3N4 additions were carried out to evaluate its effectiveness as a seeding aid for β-sialon formation. Such seeding mechanisms were effective in the Nd system but did not have a significant influence on βsialon development in the Gd and Yb systems.

Original languageEnglish
Pages (from-to)225-230
Number of pages6
JournalMaterials Science Forum
Volume325-326
Publication statusPublished - 2000
Externally publishedYes

Fingerprint

sialon
heat treatment
Heat treatment
inoculation
Garnets
Crystallization
garnets
Rare earths
Cations
rare earth elements
Positive ions
crystallization
cations
microstructure
Microstructure
composite materials
Composite materials

Keywords

  • α-sialons
  • A-β transformation
  • Heat-treatment
  • Microstructure
  • Seeding
  • Stability

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Microstructural development of Nd, Gd and Yb-Doped α'/β' sialons. / Nordmann, A.; Jumali, Mohammad Hafizuddin.

In: Materials Science Forum, Vol. 325-326, 2000, p. 225-230.

Research output: Contribution to journalArticle

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