Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

A new view of the onset of plasticity during the nanoindentation of aluminium


In nanoscale contact experiments, it is generally believed that the shear stress at the onset of plasticity can approach the theoretical shear strength of an ideal, defect-free lattice1,2,3,4, a trend also observed in idealized molecular dynamics simulations5,6,7,8,9. Here we report direct evidence that plasticity in a dislocation-free volume of polycrystalline aluminium can begin at very small forces, remarkably, even before the first sustained rise in repulsive force. However, the shear stresses associated with these very small forces do approach the theoretical shear strength of aluminium (2.2 GPa). Our observations entail correlating quantitative load–displacement measurements with individual video frames acquired during in situ nanoindentation experiments in a transmission electron microscope. We also report direct evidence that a submicrometre grain of aluminium plastically deformed by nanoindentation to a dislocation density of 1014 m−2 is also capable of supporting shear stresses close to the theoretical shear strength. This result is contrary to earlier assumptions that a dislocation-free volume is necessary to achieve shear stresses near the theoretical shear strength of the material5,6,7,8,9. Moreover, our results in entirety are at odds with the prevalent notion that the first obvious displacement excursion in a nanoindentation test is indicative of the onset of plastic deformation.

Your institute does not have access to this article

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Quantitative data from an in situ TEM nanoindentation of an Al grain using a Berkovich diamond indenter.
Figure 2: Video montage taken from the in situ TEM nanoindentation of an Al grain using a Berkovich diamond indenter.
Figure 3: A shallow in situ TEM nanoindentation of an Al grain using a FIB-sculpted diamond indenter.


  1. Gane, N. & Bowden, F. P. Microdeformation of solids. J. Appl. Phys. 39, 1432–1435 (1968).

    Article  Google Scholar 

  2. Asif, S. A. S. & Pethica, J. B. Nanoindentation creep of single-crystal tungsten and gallium arsenide. Phil. Mag. A 76, 1105–1118 (1997).

    Article  Google Scholar 

  3. Gouldstone, A., Koh, H. J., Zeng, K. Y., Giannakopoulos, A. E. & Suresh, S. Discrete and continuous deformation during nanoindentation of thin films. Acta Mater. 48, 2277–2295 (2000).

    Article  Google Scholar 

  4. Kramer, D. E., Yoder, K. B. & Gerberich, W. W. Surface constrained plasticity: oxide rupture and the yield point process. Phil. Mag. A 81, 2033–2058 (2001).

    Article  Google Scholar 

  5. Gouldstone, A., Van Vliet, K. J. & Suresh, S. Nanoindentation—simulation of defect nucleation in a crystal. Nature 411, 656 (2001).

    Article  Google Scholar 

  6. Kelchner, C. L., Plimpton, S. J. & Hamilton, J. C. Dislocation nucleation and defect structure during surface indentation. Phys. Rev. B 58, 11085–11088 (1998).

    Article  Google Scholar 

  7. Tadmor, E. B., Miller, R., Phillips, R. & Ortiz, M. Nanoindentation and incipient plasticity. J. Mater. Res. 14, 2233–2250 (1999).

    Article  Google Scholar 

  8. Zimmerman, J. A., Kelchner, C. L., Klein, P. A., Hamilton, J. C. & Foiles, S. M. Surface step effects on nanoindentation. Phys. Rev. Lett. 87, 165507 (2001).

    Article  Google Scholar 

  9. Lilleodden, E. T., Zimmerman, J. A., Foiles, S. M. & Nix, W. D. Atomistic simulations of elastic deformation and dislocation nucleation during nanoindentation. J. Mech. Phys. Solids 51, 901–920 (2003).

    Article  Google Scholar 

  10. Courtney, T. H. Mechanical Behavior of Materials (McGraw-Hill, New York, 1990).

    Google Scholar 

  11. Gerberich, W. W. et al. Superhard silicon nanospheres. J. Mech. Phys. Solids 51, 979–992 (2003).

    Article  Google Scholar 

  12. Roundy, D., Krenn, C. R., Cohen, M. L. & Morris, J. W. Ideal shear strengths of fcc aluminum and copper. Phys. Rev. Lett. 82, 2713–2716 (1999).

    Article  Google Scholar 

  13. Li, J., Van Vliet, K. J., Zhu, T., Yip, S. & Suresh, S. Atomistic mechanisms governing elastic limit and incipient plasticity in crystals. Nature 418, 307–310 (2002).

    Article  Google Scholar 

  14. Friak, M., Sob, M. & Vitek, V. Ab initio study of the ideal tensile strength and mechanical stability of transition-metal disilicides. Phys. Rev. B 68, 184101 (2003).

    Article  Google Scholar 

  15. Kramer, D. et al. Yield strength predictions from the plastic zone around nanocontacts. Acta Mater. 47, 333–343 (1998).

    Article  Google Scholar 

  16. Sob, M., Friak, M., Legut, D., Fiala, J. & Vitek, V. The role of ab initio electronic structure calculations in studies of the strength of materials. Mater. Sci. Eng. A 387–389, 148–157 (2004).

    Article  Google Scholar 

  17. Friak, M., Sob, M. & Vitek, V. Ab initio calculation of tensile strength in iron. Phil. Mag. 83, 3529–3537 (2003).

    Article  Google Scholar 

  18. Krenn, C. R., Roundy, D., Cohen, M. L., Chrzan, D. C. & Morris, J. W. Connecting atomistic and experimental estimates of ideal strength. Phys. Rev. B 65, 13411 (2002).

    Article  Google Scholar 

  19. Morris, J. W. et al. Elastic stability and the limits of strength. Thermec’2003, Pts 1-5 426–4, 4429–4434 (2003).

    Google Scholar 

  20. Fischer-Cripps, A. C. Nanoindentation (Springer, New York, 2004).

    Book  Google Scholar 

  21. Kiely, J. D., Jarausch, K. F., Houston, J. E. & Russell, P. E. Initial stages of yield in nanoindentation. J. Mater. Res. 14, 2219–2227 (1999).

    Article  Google Scholar 

  22. Minor, A. M., Morris, J. W. & Stach, E. A. Quantitative in situ nanoindentation in an electron microscope. Appl. Phys. Lett. 79, 1625–1627 (2001).

    Article  Google Scholar 

  23. Minor, A. M., Lilleodden, E. T., Stach, E. A. & Morris, J. W. In-situ transmission electron microscopy study of the nanoindentation behavior of Al. J. Electr. Mater. 31, 958–964 (2002).

    Article  Google Scholar 

  24. Minor, A. M., Lilleodden, E. T., Stach, E. A. & Morris, J. W. Direct observations of incipient plasticity during nanoindentation of Al. J. Mater. Res. 19, 176–182 (2004).

    Article  Google Scholar 

  25. Warren, O. L., Downs, S. A. & Wyrobek, T. J. Challenges and interesting observations associated with feedback-controlled nanoindentation. Z. Metallkd. 95, 287–296 (2004).

    Article  Google Scholar 

  26. Oliver, W. C. & Pharr, G. M. An improved technique for determining hardness and elastic-modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564–1583 (1992).

    Article  Google Scholar 

  27. Mullins, W. W. Theory of thermal grooving. J. Appl. Phys. 28, 333–339 (1957).

    Article  Google Scholar 

  28. Johnson, K. L. Contact Mechanics (Cambridge Univ. Press, New York, 1996).

    Google Scholar 

  29. Uchic, M. D., Dimiduk, D. M., Florando, J. N. & Nix, W. D. Sample dimensions influence strength and crystal plasticity. Science 305, 986–989 (2004).

    Article  Google Scholar 

Download references


The authors acknowledge that the research was supported in part by a US Department of Energy SBIR grant (DE-FG02-04ER83979) awarded to Hysitron, which does not constitute an endorsement by DOE of the views expressed in the article. This work was also supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under Contract No. DE-AC02-05CH11231.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Oden L. Warren.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary video S1 (MOV 2353 kb)

Supplementary Information

Supplementary figure S2 (PDF 791 kb)

Supplementary Information

Supplementary video S3 (MOV 1547 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Minor, A., Syed Asif, S., Shan, Z. et al. A new view of the onset of plasticity during the nanoindentation of aluminium. Nature Mater 5, 697–702 (2006).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

Further reading


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing