On the Experimental Determination of CTOD Based R-Curves

  • D. Hellmann
  • K.-H. Schwalbe


It is demonstrated that the British Standard BS 5762 for measuring the crack tip opening displacement (CTOD) can be modified such that the resulting CTOD is equal to the CTOD measured at the fatigue crack tip. The modifications consist of accounting for crack growth and adjustment of the rotation factor to the material under consideration. The results obtained on six different materials show that the rotation factor depends slightly on the material and is independent of specimen type, crack length, specimen thickness, and amount of crack growth.


Crack Length Crack Mouth Rotation Factor Clip Gage Single Edge Notch Bend 
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Copyright information

© Springer-Verlag Berlin, Heidelberg 1986

Authors and Affiliations

  • D. Hellmann
    • 1
  • K.-H. Schwalbe
    • 1
  1. 1.GKSS Research Center GeesthachtGeesthachtFederal Republic of Germany

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