Published August 1989 | Version v1
Journal article

Effect of nonstoichiometry on fracture toughness and hardness of yttrium oxide ceramics

  • 1. Institut National des Sciences Appliques Lyon, Groupe d'Etudes de Metallurgie Physique et Physique des Materiause, Unite Associee 341, Batiment 502, 69621 Villeurbanne Cedex (France)
  • 2. Tsinghua Univ., Beijing, BJ (China)
  • 3. Commissariat a l'Energie Atomique-Institute de Recherche et de Developpement Industrial-Centre d'Etudes Nucleaires Saclay, 91191 Gif sur Yvette Cedex (France)
  • 4. Laboratoire de Microscopie et Diffraction Electronique, Faculte des Sciences et Techniques de St Jerome, 13397 Marseille Cedex (France)

Description

This work deals with the changes in mechanical properties of yttrium oxide ceramics induced by nonstoichiometry. The maximum fracture toughness Κic, is observed at the stoichiometric composition. For an oxygen-deficient ceramic, a decrease of Κic is observed from 3.5 to 2.3 MPa.m12/. On the other hand, the Vickers hardness seems to be less dependent on stoichiometry. These results are discussed in the frame of the evolution of the Y-O bond with the stoichiometry. They set in particular the problem of the role of electrostatic energy stored in a brittle material containing charged defects in the energy balance controlling crack propagation

Additional details

Publishing Information

Journal Title
Journal of the American Ceramic Society
Journal Volume
72
Journal Issue
8
Series
J. Am. Ceram. Soc.
Journal Page Range
1562-1563
ISSN
0002-7820
CODEN
JACTA