Dislocation density evolution during high pressure torsion of a nanocrystalline Ni-Fe alloy
- Los Alamos National Laboratory
- NON LANL
High-pressure torsion (HPT) induced dislocation density evolution in a nanocrystalline Ni-20wt.%Fe alloy was investigated using X-ray diffraction and transmission electron microscopy. Results suggest that the dislocation density evolution is different from that in coarse-grained materials. An HPT process first reduces the dislocation density within nanocrystalline grains and produces a large number of dislocations located at small-angle sub grain boundaries that are formed via grain rotation and coalescence. Continuing the deformation process eliminates the sub grain boundaries but significantly increases the dislocation density in grains. This phenomenon provides an explanation of the mechanical behavior of some nanostructured materials.
- Research Organization:
- Los Alamos National Laboratory (LANL)
- Sponsoring Organization:
- DOE
- DOE Contract Number:
- AC52-06NA25396
- OSTI ID:
- 962322
- Report Number(s):
- LA-UR-09-01418; LA-UR-09-1418
- Journal Information:
- Applied Physics Letters, Journal Name: Applied Physics Letters; ISSN APPLAB; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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