Chapter 36. Fracture Toughness and Slow Crack Growth Behavior of Ni-YSZ and YSZ as a Function of Porosity and Temperature

  1. Narottam P. Bansal,
  2. Andrew Wereszczak and
  3. Edgar Lara-Curzio
  1. M. Radovic,
  2. E. Lara-Curzio and
  3. G. Nelson

Published Online: 26 MAR 2008

DOI: 10.1002/9780470291337.ch36

Advances in Solid Oxide Fuel Cells II: Ceramic Engineering and Science Proceedings, Volume 27, Issue 4

Advances in Solid Oxide Fuel Cells II: Ceramic Engineering and Science Proceedings, Volume 27, Issue 4

How to Cite

Radovic, M., Lara-Curzio, E. and Nelson, G. (2006) Fracture Toughness and Slow Crack Growth Behavior of Ni-YSZ and YSZ as a Function of Porosity and Temperature, in Advances in Solid Oxide Fuel Cells II: Ceramic Engineering and Science Proceedings, Volume 27, Issue 4 (eds N. P. Bansal, A. Wereszczak and E. Lara-Curzio), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470291337.ch36

Author Information

  1. Metals and Ceramics, Oak Ridge National Laboratory Oak Ridge, TN 37831-6069

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 2006

ISBN Information

Print ISBN: 9780470080542

Online ISBN: 9780470291337

SEARCH

Keywords:

  • velocity;
  • geometry;
  • propagation;
  • microstructure;
  • temperature

Summary

In this paper we report on the fracture toughness of YSZ and Ni-YSZ and slow-crack growth behavior of Ni-YSZ at 20°C, 600°C and 800°C. Results are presented for tests carried-out in air for YSZ and in a gas mixture of 4%H2 and 96%Ar for Ni-YSZ containing various levels of porosity. The double-torsion test method was utilized to determine the fracture toughness from the peak load obtained during fast loading test specimens that had been precracked, while crack velocity versus stress intensity curves were obtained in the doubletorsion using the load relaxation method. It was found that fracture toughness of these materials decreases with temperature and in the case of Ni-YSZ it also decreases with increasing porosity. The effect of temperature and microstructure, which was characterized by Scanning Electron Microscopy, on the fracture behavior of these materials, is discussed.