Cyclic-loading-induced Accumulation of the Geometrically Necessary Dislocations Near the Grain Boundaries of the Ni-Based Superalloy

Journal Article · Thu Jan 01 00:00:00 EST 2009 · Journal of Metals

DOI:https://doi.org/10.1007/s11837-009-0181-9· OSTI ID:971590

Huang, E-Wen ^[1]; Barabash, Rozaliya ^[1]; Ice, Gene E ^[1]; Liu, Wenjun ^[1]; Liu, Yee-Lang ^[2]; Kai, Ji-Jung ^[2]; Liaw, Peter K ^[3]

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1. ORNL
2. National Tsing Hua University, Taiwan
3. University of Tennessee, Knoxville (UTK)

In this study, a nickel-based polycrystalline superalloy is subjected to cyclic loading. The fatigue-induced microstructure is characterized by novel polychromatic X-ray microdiffraction (PXM) together with in-situ neutron diffraction and TEM. In-situ neutron strain measurements reveal two distinct stages of the fatigue damage. Three-dimensional (3D) spatially-resolved PXM micro-Laue measurements demonstrate the development of local texture and formation of geometrically necessary dislocations near the grain boundaries, which is accompanied by lattice rotations and grain subdivisions. The PXM results are in agreement with the in-situ neutron diffraction and TEM results.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 971590
• Journal Information: Journal of Metals, Vol. 61, Issue 12; ISSN 0148-6608
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DISLOCATIONS
GRAIN BOUNDARIES
HEAT RESISTING ALLOYS
MICROSTRUCTURE
NEUTRON DIFFRACTION
NEUTRONS
STRAINS
TEXTURE
x-ray microdiffraction
fatigue
neutron diffraction