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Creep Cavitation Effects in Polycrystalline Alumina

  • J. R. Porter
  • W. Blumenthal
  • A. G. Evans
Part of the Materials Science Research book series (MSR, volume 14)

Abstract

Fine grained polycrystalline alumina has been deformed in creep at high temperatures, to examine the evolution of cavities at grain boundaries. Cavities with equilibrium and crack-like morphologies have been observed, distributed non-uniformly throughout the material. The role of these cavities during creep has been described. A transition from equilibrium to crack-like morphology has been observed and correlated with a model based on the influence of the surface to boundary diffusivity ratio and the local tensile stress. The contribution of cavitation to the creep rate and total creep strain has been analyzed and excluded as the principal cause of the observed non-linear creep rate.

Keywords

Creep Rate Creep Deformation Cavity Growth Diffusional Creep Cavitation Model 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1981

Authors and Affiliations

  • J. R. Porter
    • 1
  • W. Blumenthal
    • 1
  • A. G. Evans
    • 1
  1. 1.Materials and Molecular Research Division Lawrence Berkeley Laboratory, and Department of Materials Science and Mineral EngineeringUniversity of CaliforniaBerkeleyUSA

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