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Structural Details of Sialons — Their Influence on Phase Stability

  • Jörgen Sjöberg
  • Robert Pompe
Chapter

Abstract

In view of the importance for phase relationships, preparation and properties, details of the structures of O’-sialons and β’-sialons have been studied. In addition to conventional powder x-ray diffraction, more recently developed techniques have been used: Neutron powder diffraction for determination of site occupancies; MAS NMR and EXAFS to study local atomic arrangements. The results are compared to literature data from related work. It is proposed that there exists a certain degree of local ordering in O’- and β’-sialon structures, and that this sets limits on the ranges of solid solubility for the two phases. This may also affect the strength of sialon grains in the matrix.

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Copyright information

© Elsevier Science Publishers Ltd and MPA Stuttgart 1992

Authors and Affiliations

  • Jörgen Sjöberg
    • 1
  • Robert Pompe
    • 1
  1. 1.Department of Inorganic ChemistryChalmers University of Technology and University of Göteborg, and Swedish Ceramic InstituteGöteborgSweden

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