Materials Science

, Volume 48, Issue 1, pp 12–19 | Cite as

Method for the determination of the characteristics of crack resistance of elastoplastic materials

  • Ya. L. Ivanyts’kyi
  • S. Т. Shtayura
  • M. Kowalik

We propose a procedure for the determination of the level of strains, the length of the plastic zone, and crack-tip opening displacements based on the use of the digital speckle-correlation method and the data of strain-gauge measurements under the conditions of uniaxial and biaxial tension of a plate weakened by a central crack. It is experimentally established that the size of the plastic zone near the crack tip for a given material is independent of the gauge length but changes if we pass to biaxial loading. On the basis of the solution of the elastoplastic problem of limiting equilibrium of a plate weakened by a crack obtained within the framework of the δ c -model, we deduce the formula for the evaluation the mean value of crack resistance of the material (\( {\tilde{\delta }_c} \)) and the length of the plastic zone (lp *). The influence of biaxial loading on the size of this zone is estimated.


crack-tip opening displacements strains in the process zone length of the plastic zone digital correlation of speckle images uniaxial and biaxial loading 


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Copyright information

© Springer Science+Business Media, Inc. 2012

Authors and Affiliations

  • Ya. L. Ivanyts’kyi
    • 1
  • S. Т. Shtayura
    • 1
  • M. Kowalik
    • 2
  1. 1.Karpenko Physicomechanical InstituteUkrainian National Academy of SciencesLvivUkraine
  2. 2.Technical University of RadomRadomPoland

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