Abstract
The indentation size effect in spherical indentation experiments is studied via the conventional theory of mechanism-based strain gradient plasticity (CMSG) established from the Taylor dislocation model. Two approaches are adopted in the present study. The first, an extension of Johnson's [Johnson, K.L., 1970. The correlation of indentation experiments. Journal of the Mechanics and Physics of Solids 18, 115-126.] theoretical indentation model based on CMSG, fails to predict the experimental data for iridium. The finite element method for CMSG is used to characterize the indented material in the second approach. The predicted indentation hardness agrees well with the experimental data. A simple, analytic indentation model is established to give the indentation hardness H=H02+141α2μ2bR in terms of the radius R of the spherical indenter, where H 0 is the indentation hardness without accounting for the tip radius effect (i.e., given by classical plasticity theories), μ is the shear modulus, b is the magnitude of the Burgers vector, and α is the empirical coefficient around 1/3 in the Taylor dislocation model.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1265-1286 |
| Number of pages | 22 |
| Journal | International journal of plasticity |
| Volume | 22 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 1 2006 |
Fingerprint
Keywords
- Indentation size effect
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering
Cite this
}
The indentation size effect in the spherical indentation of iridium : A study via the conventional theory of mechanism-based strain gradient plasticity. / Qu, S.; Huang, Y.; Pharr, G. M.; Hwang, K. C.
In: International journal of plasticity, Vol. 22, No. 7, 01.07.2006, p. 1265-1286.Research output: Contribution to journal › Article
TY - JOUR
T1 - The indentation size effect in the spherical indentation of iridium
T2 - A study via the conventional theory of mechanism-based strain gradient plasticity
AU - Qu, S.
AU - Huang, Y.
AU - Pharr, G. M.
AU - Hwang, K. C.
PY - 2006/7/1
Y1 - 2006/7/1
N2 - The indentation size effect in spherical indentation experiments is studied via the conventional theory of mechanism-based strain gradient plasticity (CMSG) established from the Taylor dislocation model. Two approaches are adopted in the present study. The first, an extension of Johnson's [Johnson, K.L., 1970. The correlation of indentation experiments. Journal of the Mechanics and Physics of Solids 18, 115-126.] theoretical indentation model based on CMSG, fails to predict the experimental data for iridium. The finite element method for CMSG is used to characterize the indented material in the second approach. The predicted indentation hardness agrees well with the experimental data. A simple, analytic indentation model is established to give the indentation hardness H=H02+141α2μ2bR in terms of the radius R of the spherical indenter, where H 0 is the indentation hardness without accounting for the tip radius effect (i.e., given by classical plasticity theories), μ is the shear modulus, b is the magnitude of the Burgers vector, and α is the empirical coefficient around 1/3 in the Taylor dislocation model.
AB - The indentation size effect in spherical indentation experiments is studied via the conventional theory of mechanism-based strain gradient plasticity (CMSG) established from the Taylor dislocation model. Two approaches are adopted in the present study. The first, an extension of Johnson's [Johnson, K.L., 1970. The correlation of indentation experiments. Journal of the Mechanics and Physics of Solids 18, 115-126.] theoretical indentation model based on CMSG, fails to predict the experimental data for iridium. The finite element method for CMSG is used to characterize the indented material in the second approach. The predicted indentation hardness agrees well with the experimental data. A simple, analytic indentation model is established to give the indentation hardness H=H02+141α2μ2bR in terms of the radius R of the spherical indenter, where H 0 is the indentation hardness without accounting for the tip radius effect (i.e., given by classical plasticity theories), μ is the shear modulus, b is the magnitude of the Burgers vector, and α is the empirical coefficient around 1/3 in the Taylor dislocation model.
KW - Indentation size effect
UR - http://www.scopus.com/inward/record.url?scp=33344475846&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33344475846&partnerID=8YFLogxK
U2 - 10.1016/j.ijplas.2005.07.008
DO - 10.1016/j.ijplas.2005.07.008
M3 - Article
VL - 22
SP - 1265
EP - 1286
JO - International Journal of Plasticity
JF - International Journal of Plasticity
SN - 0749-6419
IS - 7
ER -