Chapter 12. Parametric Study of Notch Geometry in Standardized Chevron Notched Fracture Test Specimens for Advanced Ceramics

  1. Hua-Tay Lin and
  2. Mrityunjay Singh
  1. Franz Nigl1,
  2. Michael Jenkins1 and
  3. Jonathan Salem2

Published Online: 26 MAR 2008

DOI: 10.1002/9780470294741.ch12

26th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: A: Ceramic Engineering and Science Proceedings, Volume 23, Issue 3

26th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: A: Ceramic Engineering and Science Proceedings, Volume 23, Issue 3

How to Cite

Nigl, F., Jenkins, M. and Salem, J. (2002) Parametric Study of Notch Geometry in Standardized Chevron Notched Fracture Test Specimens for Advanced Ceramics, in 26th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: A: Ceramic Engineering and Science Proceedings, Volume 23, Issue 3 (eds H.-T. Lin and M. Singh), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470294741.ch12

Author Information

  1. 1

    University of Washington Mechanical Engineering Bldg Box 352600 Seattle, WA 98195–2600

  2. 2

    NASA-Glenn Research Center 21000 Brookpark Rd MS 49–7 Cleveland, OH 49135

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 2002

ISBN Information

Print ISBN: 9780470375785

Online ISBN: 9780470294741

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Keywords:

  • parameters;
  • assumption;
  • determination;
  • stress intensity factor (SIF);
  • dimensions

Summary

The purpose of this study was to determine the relative influences of selected geometric parameters on the resulting stress intensity factor geometry correction factor, Y, for chevron notched fracture test specimens, stable crack propagation during the test and stability of the resulting fracture process. Finite element analysis (FEA) was used to model test specimen geometries specialized in American Society for Testing and Materials (ASTM) Standard Test Method C 1421 [1]. Geometric parameters studied include notch thickness, notch corner radius, notch symmetry, notch centering, test specimen width and test specimen thickness. The results showed that the allowed notch thickness should not be increased. The assumption that the influence of the test specimen width is small is correct. The calculations showed that the eccentricity of the notch has no influence on Y. The results for the symmetry were good for the lower limits, and the difference to the ASTM values was less than two percent. The biggest differences were for the changes in the specimen height. The differences of the FEA results compared to the ASTM values were up to five percent. The study of the crack stability showed that the notch can not be modeled ideal with a sharp notch and that the importance of the crack initiation.