Metallurgical and Materials Transactions A

, Volume 38, Issue 13, pp 2214–2225

Fatigue Crack Initiation In WASPALOY at 20 °C

  • D. L. Davidson
  • R. G. Tryon
  • M. Oja
  • R. Matthews
  • K. S. Ravi Chandran
SYMPOSIUM: Deformation & Fracture from Nano to Macro: Honoring W.W. Gerberich’s 70th Birthday

In two WASPALOY specimens, the orientations of grains that initiated fatigue cracks and adjacent ograins were measured using electron backscattered diffraction patterns (EBSP). Crystallographic relationships were found for crack initiating regions that resulted in slip transmission across areas larger than the initiating grain, and the initiating grain was usually larger than average. A similar evaluation of control areas on each specimen found that there was much less likelihood of slip transmission across grain boundaries. Schmid factors (SFs) were also evaluated. It is concluded that the reason that fatigue cracks formed at these locations was due to the lower stress required for slip initiation in these clusters of grains oriented for slip transmission across grain boundaries. Many of the cracks initiated within grain boundaries. A detailed crystallographic analysis of the adjacent grains suggests criteria for intergranular (IG) crack initiation.

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Copyright information

© THE MINERALS, METALS & MATERIALS SOCIETY and ASM INTERNATIONAL 2007

Authors and Affiliations

  • D. L. Davidson
    • 1
  • R. G. Tryon
    • 2
  • M. Oja
    • 2
  • R. Matthews
    • 2
  • K. S. Ravi Chandran
    • 3
  1. 1.San AntonioUSA
  2. 2.VEXTEC CorporationBrentwoodUSA
  3. 3.Department of Metallurgical EngineeringThe University of UtahSalt Lake CityUSA

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