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Microstructure and Properties of Mixed α’+β’-Sialons

  • G. Z. Cao
  • R. Metselaar
  • G. Ziegler
Chapter

Abstract

The microstructure and mechanical properties of fully dense yttrium-containing α’ + β’-sialon ceramics prepared by gas pressure sintering were studied. The typical microstructure of mixed α’+β’-sialon ceramics consists of needle-like grains of the β’-phase (the ratio of length to width is about 7) dispersed in a matrix of equi-axed α’-sialon grains (mean grain size is about 3 µm) with a small fraction of an yttrium-rich amorphous phase (atom ratio Y:Si:Al = 0.8: 1.0:0.5) at grain boundaries. Vickers hardness (HvO.5) and fracture toughness (KIC) were measured by using the indentation technique and the biaxial bending strength (σbi) was determined with the “ball-on-ring” test. The relationships between the composition, microstructure and mechanical properties are discussed.

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Copyright information

© Elsevier Science Publishers Ltd and MPA Stuttgart 1992

Authors and Affiliations

  • G. Z. Cao
    • 1
  • R. Metselaar
    • 1
  • G. Ziegler
    • 2
  1. 1.Eindhoven University of Technologythe Netherlands
  2. 2.Bayreuth UniversityBayreuthF.R. Germany

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