Crack-Tip Plastic Zone Size and Shape via DIC

  • G. L. G. Gonzáles
  • J. A. O. González
  • V. E. L. Paiva
  • J. L. F. Freire
Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)


In this paper Digital Image Correlation (DIC) is used to characterize the crack-tip plastic zone size and shape under plane stress and plane strain situations. For that, two disk-shaped tension DC(T) specimens made of 1020 steel with thicknesses 2 and 30 mm were used in fatigue crack growth tests to simulated plane stress and plane strain conditions, respectively. Fatigue cracks were grown under quasi-constant ΔK (stress intensity factor range) and stress ratio (R) respectively equal to 20 MPa√m and 0.1. A single 100% overload was applied when the crack reached a crack length of 6 mm (i.e. total crack length/specimen width = 0.3). Experimental measurements of the monotonic plastic zone at different stages during overload application are compared with finite elements simulations to predict the size and shape of the crack-tip plastic zone. A detailed discussion is given based on the DIC measurements obtained from the current investigation, including the experimental observations of crack closure.


Plastic zone Crack closure Fatigue crack Digital Image Correlation 


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Copyright information

© The Society for Experimental Mechanics, Inc. 2019

Authors and Affiliations

  • G. L. G. Gonzáles
    • 1
  • J. A. O. González
    • 1
  • V. E. L. Paiva
    • 1
  • J. L. F. Freire
    • 1
  1. 1.Pontifical Catholic University of Rio de Janeiro, PUC-RioRio de JaneiroBrazil

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