Inclusions Effect on the Notch Behaviour of a Low-Alloy Tempered Steel

  • R. Doglione
  • D. Firrao
Part of the NATO Science Series book series (NAII, volume 11)


A previous model describing ductile fracture initiation ahead of sharp crack as well as blunt notches is discussed. Its application to a quenched and tempered Ni-Cr-Mo steel led to a relationship between fracture toughness, inclusions spacing, strain hardening exponent and notch root radius p. This relationship was formulated on the hypothesis of constant (i.e. independent on p) critical notch root strain. It has been found that the independence of the critical notch root strain is consistent with the critical void growth ratio criterion for ductile fracture, thus substantiating the model on a micromechanical basis. Finally, the toughness-notch radius relationship, combined together with the EPRI J estimation scheme, has been used to propose a method for the calculation of ductile fracture initiation in notched structural components.


Fracture Toughness Ductile Fracture Linear Elastic Fracture Mechanics Void Growth Notch Root 
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Copyright information

© Springer Science+Business Media Dordrecht 2001

Authors and Affiliations

  • R. Doglione
    • 1
  • D. Firrao
    • 1
  1. 1.Politecnico di TorinoTorinoItaly

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