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Analysis of nanoindentation load-displacement loading curves

Published online by Cambridge University Press:  31 January 2011

S. V. Hainsworth
Affiliation:
Materials Division, Department of Mechanical, Materials and Manufacturing Engineering, University of Newcastle upon Tyne, Newcastle upon Tyne, NE1 7RU, United Kingdom
H. W. Chandler
Affiliation:
Materials Division, Department of Mechanical, Materials and Manufacturing Engineering, University of Newcastle upon Tyne, Newcastle upon Tyne, NE1 7RU, United Kingdom
T. F. Page
Affiliation:
Materials Division, Department of Mechanical, Materials and Manufacturing Engineering, University of Newcastle upon Tyne, Newcastle upon Tyne, NE1 7RU, United Kingdom
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Abstract

Nanoindentation load-displacement curves provide a “mechanical fingerprint” of a materials response to contact deformation. Over the last few years, much attention has been focused on understanding the factors controlling the detailed shape of unloading curves so that parameters such as true contact area, Young's modulus, and an indentation hardness number can be derived. When the unloading curve is well behaved (by which we mean approximating to linear behavior, or alternatively, fitting a power-law relationship), then this approach can be very successful. However, when the test volume displays considerable elastic recovery as the load is removed [e.g., for many stiff hard materials and many inhomogeneous systems (e.g., those employing thin hard coatings)], then the unloading curve fits no existing model particularly well. This results in considerable difficulty in obtaining valid mechanical property data for these types of materials. An alternative approach, described here, is to attempt to understand the shapes of nanoindentation loading curve and thus quantitatively model the relationship between Young's modulus, indentation hardness, indenter geometry, and the resultant maximum displacement for a given load. This paper describes the development and refinement of a previous approach by Loubet et al1 originally suggested for a Vickers indenter, but applied here to understand the factors that control the shape of the loading curve during nanoindentation experiments with a pointed, trigonal (Berkovich) indenter. For a range of materials, the relationship P = Kmδ2 was found to describe the indenter displacement, δ, in terms of the applied load P. For each material, Km can be predicted from the Young's modulus (E) and the hardness (H). The result is that if either E or H is known, then the other may be calculated from the experimental loading curve. This approach provides an attractive alternative to finite element modeling and is a tractable approach for those cases where analysis of unloading curves is infeasible.

Type
Articles
Copyright
Copyright © Materials Research Society 1996

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References

REFERENCES

1.Loubet, J. L., Georges, J.M., and Meille, J., in Microindentation Techniques in Materials Science and Engineering, edited by Blau, P. J. and Lawn, B. R. (American Society for Testing and Materials, Philadelphia 1986), pp. 7289.Google Scholar
2.Page, T.F. and Hainsworth, S.V., Surf. Coatings Technol. 68/69, 571575 (1994).Google Scholar
3.McGurk, M. R., Chandler, H. W., Twigg, P. C., and Page, T. F., Surf. Coatings Technol. 68/69, 576581 (1994).CrossRefGoogle Scholar
4.Doerner, M. F. and Nix, W. D., J. Mater. Res. 1, 601609 (1986).CrossRefGoogle Scholar
5.Oliver, W. C. and Pharr, G. M., J. Mater. Res. 7, 15641583 (1992).CrossRefGoogle Scholar
6.Pharr, G. M., Tsui, T. Y., Bolshakov, A., and Oliver, W. C., in Materials Reliability in Microelectronics IV, edited by Børgesen, P., Coburn, J. C., Sanchez, J. E. Jr., and Rodbell, K. P., and Filter, W. F. (Mater. Res. Soc. Symp. Proc. 338, Pittsburgh, PA, 1994), pp. 127134.Google Scholar
7.Swain, M. V. and Menčík, J., Thin Solid Films 253, 204211 (1994).CrossRefGoogle Scholar
8.Hainsworth, S. V., Whitehead, A. J., and Page, T. F., in Plastic Deformation of Ceramics, edited by Bradt, R. C., Brookes, C. A., and Routbort, J.L., Proc. Int. Conf. Snowbird, Utah, August 7–12, 1994 (Plenum Publ. Corp., New York, 1995), pp. 173184.CrossRefGoogle Scholar
9.Page, T. F., Oliver, W. C., and McHargue, C. J., J. Mater. Res. 7, 450472 (1992).CrossRefGoogle Scholar
10.Hainsworth, S. V. and Page, T. F., J. Mater. Sci. 29, 55295540 (1994).CrossRefGoogle Scholar
11.Sargent, P. M. and Page, T. F., Proc. Brit. Ceram. Soc. 26, 209224 (1978).Google Scholar
12.Bull, S. J., Page, T. F., and Yoffe, E. H., Phil. Mag. Lett. 59, 281288 (1989).CrossRefGoogle Scholar
13.Hainsworth, S. V., Chandler, H. W., and Page, T. F., unpublished.Google Scholar
14.Hainsworth, S. V., and Page, T. F., in Thin films: Stresses and Mechanical Properties VI, edited by Gerberich, W. W., Sundgren, J-E., Gao, H., and Baker, S. P. (Mater. Res. Soc. Symp. Proc. 1996), in press.Google Scholar
15.Greenwood, J. A. and Williamson, J.B. P., Proc. Roy. Soc. London A295, 300319 (1966).Google Scholar
16.Sjöström, H., Hultman, L., Sundgren, J-E., Hainsworth, S. V., Page, T. F., and Theunissen, G. S. A. M., J. Vac. Sci. Technol. in J Vac Sci Technol. A. 14, 17 (1996).Google Scholar
17.Field, J. S. and Swain, M. V., J. Mater. Res. 8, 297306 (1993).CrossRefGoogle Scholar