Influence of fatigue crack wake length and state of stress on crack closureThe location of crack closure with respect to crack wake and specimen thickness under different loading conditions was determined. The rate of increase of K sub CL in the crack wake was found to be significantly higher for plasticity induced closure in comparison to roughness induced closure. Roughness induced closure was uniform throughout the thickness of the specimen while plasticity induced closure levels were 50 percent higher in the near surface region than in the midthickness. The influence of state of stress on low-high load interaction effects was also examined. Load interaction effects differed depending upon the state of stress and were explained in terms of delta K sub eff.
Document ID
19890030061
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Telesman, Jack (NASA Lewis Research Center Cleveland, OH, United States)
Fisher, Douglas M. (NASA Lewis Research Center Cleveland, OH, United States)