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JOM

, Volume 37, Issue 1, pp 54–57 | Cite as

Experimental Characterization of Fatigue Crack Tip Processes

  • J. Lankford
  • G. R. Leverant
Physical & Mechanical Metallurgy
  • 34 Downloads

Summary

Many analytical models have been proposed to describe the physical processes attendant to a fatigue crack tip, as well as the rate at which fatigue cracks grow. By applying advanced experimental methods (such as electron channeling, stereoimaging, and in-situ cyclic loading in an SEM) to a broad range of structural materials, it has been shown that it is possible to critically assess the physical assumptions incorporated into the models. Refinements in existing models and the development of new ones have resulted. New insights into materials’ behavior are providing guidelines for improving the fatigue resistance of structural alloys. In the near future, even more advanced experimental methods, such as high temperature SEM stages and small angle neutron scattering, will be available to study creep/fatigue interactions in metals and ceramics.

Keywords

Fatigue Crack Fatigue Crack Growth Linear Elastic Fracture Mechanic Southwest Research Institute Effective Stress Intensity Range 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© TMS 1985

Authors and Affiliations

  • J. Lankford
    • 1
  • G. R. Leverant
    • 1
  1. 1.Department of Materials Sciences at Southwest Research InstituteSan AntonioUSA

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