Abstract
The onset of plasticity during nanoindentation of a tungsten single crystal was examined as a function of pre-existing dislocation density. Vickers indentations were used to generate a spatially varying dislocation density, and nanoindentation was then carried out at regions of high and low dislocation densities. Even with dislocation densities as high as 1.8 × 1013 m−2, a sharp elastic-plastic transition was observed during some indentations. At lower dislocation densities, 3.5 × 109 m−2, the shear stress at the elastic plastic transition increased and approached the theoretical shear stress of the crystal. A first-order model that predicts the load required for the onset of plasticity during nanoindentation from the activation of a dislocation source within a critical volume of material, rather than homogeneous dislocation nucleation, is developed. The model correlates well with experimentally measured loads at the onset of plasticity for dislocation densities of 1012 m−2 and higher for these nanoindentation conditions.
Similar content being viewed by others
References
N. Gane, F.P. Bowden: J. Appl. Phys., 1967, vol. 39, pp.1432–35
J. Pethica, D. Tabor: Surf. Sci., 1979, vol. 89, pp. 182–90
A.B. Mann, J.B. Pethica: Appl. Phys. Lett., 1996, vol. 69, pp. 907–09
W.W. Gerberich, J.C. Nelson, E.E. Lilleodden, P. Anderson, J.T. Wyrobek: Acta Mater., 1996, vol. 44, pp. 3585–98
S.A. Syed-Asif, J.B. Pethica: Phil. Mag. A, 1997, vol. 76, pp. 1105–18
D.F. Bahr, D.E. Kramer, W.W. Gerberich: Acta Mater., 1998, vol. 46, pp. 3605–17
Y. Chiu and A. Ngan: Acta Mater., 2002, vol. 50, 1599–11
J. Bradby, J. William, M. Swain: J. Mater. Res., 2003, vol. 19, pp. 380–86
C.A. Schuh: Nat. Mater., 2005, vol. 4, pp. 617–22
C.L. Kelchner, S.J. Plimpton, J.C. Hamilton: Phys. Rev. B, 1998, vol. 58, pp. 11085–11088
D. Rodriquez-Marek, M. Pang, D.F. Bahr: Metall. Mater. Trans. A, 2003, vol. 34A, 1291–96
M. Pang, D.F. Bahr: J. Mater. Res., 2001, vol. 16, pp. 2634–43
E. Weppelmann, M.V. Swain: Thin Solid Films, 1996, vol. 286, pp. 111–21
S.V. Hainsworth, M.R. McGurk, T.F. Page: Surf. Coat. Technol., 1998, vol. 102, pp. 97–107
D.E. Kramer, K.B. Yoder, W.W. Gerberich: Phil. Mag. A, 2001, vol. 81, pp. 2033–58
G.F. Vander Voort: Metallography Principles and Practice, McGraw-Hill, New York, NY, 1984, pp. 599 and 697
Y. Shibutani, A. Koyama: J. Mater. Res., 2003, vol. 19, pp. 183–88
S. Amelinckx: Phil. Mag., 1956, vol. 1, pp. 269–90
K.L. Johnson: Contact Mechanics, Cambridge University Press, New York, NY, 1985, pp. 90–104
N. Stelmashenko, M.G. Walls, L.M. Brown, and Yu.V. Milman: Acta Metall. Mater., 1993, vol. 46, pp. 2855–65
T. Michalske and J.E. Houston: Acta Mater., 1998, vol. 46, pp. 391–96
D.F. Bahr, D.E. Wilson, D.A. Crowson: J. Mater. Res., 1999, vol. 14, pp. 2269–75
J.G. Swadener, B. Taljit, G.M. Pharr: J. Mater. Res., 2001, vol. 16, pp. 2091–2102
Author information
Authors and Affiliations
Corresponding author
Additional information
This article is based on a presentation given in the symposium entitled “Deformation and Fracture from Nano to Macro: A Symposium Honoring W.W. Gerberich’s 70th Birthday,” which occurred during the TMS Annual Meeting, March 12–16, 2006 in San Antonio, Texas and was sponsored by the Mechanical Behavior of Materials and Nanomechanical Behavior Committees of TMS.
Rights and permissions
About this article
Cite this article
Zbib, A., Bahr, D. Dislocation Nucleation and Source Activation during Nanoindentation Yield Points. Metall Mater Trans A 38, 2249–2255 (2007). https://doi.org/10.1007/s11661-007-9284-5
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11661-007-9284-5