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Nd-Ce-TZP Powders and Ceramics: Hydrothermal Preparation of High Quality Powders from Sulphate Precursors

  • Laila Grahl-Madsen
  • Nanna Petersen
  • Kathryn Warner
  • Jesper Sand Damtoft
  • John Engell
Chapter

Abstract

High quality powders of tetragonal zirconia of the composition Nd0.01 Ce0.08 Zr0.91 O2-x have been prepared hydrothermally by in-situ crystallization (best 225°C/2.4 MPa, 7–8 h, pH 10–11) of co-precipitated sulphate derived gels. The best powders contain 0.2 wt% residual SO3. Uniaxially pressed tablets of the as prepared freeze dried powders sinter to >95% TD in 1 hat 1350°C, whereas tablets of calcined and milled powders sinter to >99% TD in 1 h at 1320°C. These ceramics have an average grain size around 1 µm, a 4-point bending strength of 450 MPa, and show a pseudo-plastic behaviour. The toughness is too high to be measured by Vickers indentation. Sintering to 1400°C for 2 h results in sufficient grain growth to induce a slow spontaneous transformation of tetragonal→monoclinic zirconia upon cooling.

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Copyright information

© Elsevier Science Publishers Ltd and MPA Stuttgart 1992

Authors and Affiliations

  • Laila Grahl-Madsen
    • 1
  • Nanna Petersen
    • 1
  • Kathryn Warner
    • 1
  • Jesper Sand Damtoft
    • 2
  • John Engell
    • 1
  1. 1.Technical University of DenmarkLyngbyDenmark
  2. 2.Aalborg PortlandAalborgDenmark

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