Meccanica

, Volume 43, Issue 2, pp 201–210 | Cite as

Experimental investigation on the propagation of fatigue cracks emanating from sharp notches

  • M. Benedetti
  • M. Beghini
  • L. Bertini
  • V. Fontanari
Article
First Online:
Accepted:

Abstract

The effect of notch geometry on the propagation of fatigue cracks emanating from sharp V-shaped notches is investigated by means of an experimental campaign performed on Al-7075-T651 specimens carrying notches with opening angles of 45°, 90°, and 135°. The samples were tested using a servohydraulic machine under different loading directions and at several loading levels. The crack deflection induced by the variation in loading direction was determined my measuring the kinking angle and by studying the crack propagation plane through fractographic analysis. A linear elastic fracture mechanics approach was adopted for the analysis of experimental results. Stress intensity factors were calculated using an appropriate weight function set up for studying inclined edge cracks emanating from sharp V-notches. The influence of K II on the crack propagation was discussed on the basis of theoretical and semi empirical models.

Keywords

Fatigue crack propagation Sharp V-notches Loading direction Al-7075-T651 
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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • M. Benedetti
    • 1
  • M. Beghini
    • 2
  • L. Bertini
    • 2
  • V. Fontanari
    • 1
  1. 1.Department of Materials Engineering and Industrial TechnologiesUniversity of TrentoTrentoItaly
  2. 2.Department of Mechanical Nuclear and Production EngineeringUniversity of PisaPisaItaly

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