SYMPOSIUM: Deformation & Fracture from Nano to Macro: Honoring W.W. Gerberich’s 70th Birthday

Metallurgical and Materials Transactions A

, Volume 38, Issue 13, pp 2214-2225

First online:

Fatigue Crack Initiation In WASPALOY at 20 °C

  • D. L. DavidsonAffiliated with Email author 
  • , R. G. TryonAffiliated withVEXTEC Corporation
  • , M. OjaAffiliated withVEXTEC Corporation
  • , R. MatthewsAffiliated withVEXTEC Corporation
  • , K. S. Ravi ChandranAffiliated withDepartment of Metallurgical Engineering, The University of Utah

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

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.