Abstract
Recent interest in high-strength nanocrystalline structures has prompted a call for understanding scale effects in deformation mechanisms. One aspect, producing nanostructures by severe plastic deformation, promoted the present examination of nanoposts undergoing large strain compression. On e-beam lithography produced nanoposts of both aluminum and permalloy with radii ranging from 50 to 150 nm, single and repeat compression tests produced measurements of flow stress and apparent activation volume. Flow stresses, continuously measured with a nanoindenter allowed theoretical assessment of the deformation mechanism. It was concluded that the high stresses (1-3 GPa) and small activation volumes (1-10b3) where b is the modulus of the Burgers vector, were consistent with dislocation nucleation. A traditional model is shown to give good first order accountability for these two face-centered cubic metals.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 12-20 |
| Number of pages | 9 |
| Journal | Materials Science and Engineering A |
| Volume | 493 |
| Issue number | 1-2 |
| DOIs | |
| State | Published - Oct 15 2008 |
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Keywords
- Activation volume
- Dislocation
- Flow stress
- Nanocrystalline
- Nanoindentation
Cite this
Flow stresses and activation volumes for highly deformed nanoposts. / Mook, W. M.; Lund, M. S.; Leighton, C.; Gerberich, W. W.
In: Materials Science and Engineering A, Vol. 493, No. 1-2, 15.10.2008, p. 12-20.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Flow stresses and activation volumes for highly deformed nanoposts
AU - Mook, W. M.
AU - Lund, M. S.
AU - Leighton, C.
AU - Gerberich, W. W.
PY - 2008/10/15
Y1 - 2008/10/15
N2 - Recent interest in high-strength nanocrystalline structures has prompted a call for understanding scale effects in deformation mechanisms. One aspect, producing nanostructures by severe plastic deformation, promoted the present examination of nanoposts undergoing large strain compression. On e-beam lithography produced nanoposts of both aluminum and permalloy with radii ranging from 50 to 150 nm, single and repeat compression tests produced measurements of flow stress and apparent activation volume. Flow stresses, continuously measured with a nanoindenter allowed theoretical assessment of the deformation mechanism. It was concluded that the high stresses (1-3 GPa) and small activation volumes (1-10b3) where b is the modulus of the Burgers vector, were consistent with dislocation nucleation. A traditional model is shown to give good first order accountability for these two face-centered cubic metals.
AB - Recent interest in high-strength nanocrystalline structures has prompted a call for understanding scale effects in deformation mechanisms. One aspect, producing nanostructures by severe plastic deformation, promoted the present examination of nanoposts undergoing large strain compression. On e-beam lithography produced nanoposts of both aluminum and permalloy with radii ranging from 50 to 150 nm, single and repeat compression tests produced measurements of flow stress and apparent activation volume. Flow stresses, continuously measured with a nanoindenter allowed theoretical assessment of the deformation mechanism. It was concluded that the high stresses (1-3 GPa) and small activation volumes (1-10b3) where b is the modulus of the Burgers vector, were consistent with dislocation nucleation. A traditional model is shown to give good first order accountability for these two face-centered cubic metals.
KW - Activation volume
KW - Dislocation
KW - Flow stress
KW - Nanocrystalline
KW - Nanoindentation
UR - http://www.scopus.com/inward/record.url?scp=49849084492&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=49849084492&partnerID=8YFLogxK
U2 - 10.1016/j.msea.2007.08.096
DO - 10.1016/j.msea.2007.08.096
M3 - Article
AN - SCOPUS:49849084492
VL - 493
SP - 12
EP - 20
JO - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
JF - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
SN - 0921-5093
IS - 1-2
ER -