Journal Published Online: 14 May 2014
Volume 3, Issue 2

Creep-Fatigue-Environment Crack Tip Kinetics of Ni-Base Superalloys



Several time-dependent damage mechanisms can operate during creep-fatigue loading. In the crack tip region, creep deformation, stress relaxation, oxygen diffusion along grain boundaries, and grain boundary oxidation are all occurring during the hold period of a creep-fatigue cycle. These conditions can lead to grain boundary embrittlement; however, it depends on the rates of the different processes. A comparison of the kinetics can determine which mechanisms are operational and which mechanism is the rate limiting step in the time-dependent damage process during creep-fatigue crack growth. This paper presents results for intergranular embrittlement occurring within a 10 s hold period and compares the kinetics of the processes.

Author Information

Evans, Jeffrey
Univ. of Alabama in Huntsville, Department of Mechanical and Aerospace Engineering, Huntsville, AL, US
Pages: 7
Price: $25.00
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Stock #: MPC20130026
ISSN: 2165-3992
DOI: 10.1520/MPC20130026