Mechanical Properties of Gas Pressure Sintered Silicon Nitride

  • Cornelia Boberski
  • Rainer Hamminger


The densification behavior of Si3N4-powders during gas pressure sintering with additions of Y2O3 and Al2O3 was studied by dilatometer measurements. High densities of 99.5% of the theoretical value were achieved by 2-step gas pressure sintering while the density of pressureless sintered material was 1–2 % less. The reliability of the sintered ceramic material was improved by applying gas pressure after the main densification step. The Weibull modulus of pressureless sintered materials of m=8–11 increased to m=20–25 by applying gas pressure sintering. The average bending strength (4-point) was 800–900 MPa for pressureless as well as gas pressure sintered materials.


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Copyright information

© Elsevier Science Publishers Ltd and MPA Stuttgart 1992

Authors and Affiliations

  • Cornelia Boberski
    • 1
  • Rainer Hamminger
    • 1
  1. 1.Hoechst AGFrankfurt 80Germany

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