Hostname: page-component-7c8c6479df-p566r Total loading time: 0 Render date: 2024-03-29T13:31:11.383Z Has data issue: false hasContentIssue false

Correction factor for contact area in nanoindentation measurements

Published online by Cambridge University Press:  01 March 2005

Michel Troyon*
Affiliation:
Laboratoire de Microscopies et d'Etude de Nanostructures, EA 3799, Université de Reims, 51685 Reims Cedex 2, France
Liye Huang
Affiliation:
Laboratoire de Microscopies et d'Etude de Nanostructures, EA 3799, Université de Reims, 51685 Reims Cedex 2, France
*
a)Address all correspondence to this author. e-mail: michel.troyon@univ-reims.fr
Get access

Abstract

In the relationship between unloading contact stiffness, elastic modulus, and contact area, which is the fundamental basic equation for nanoindentation analysis, a multiplicative correction factor is generally needed. Sometimes this correction factor is called γ to take into account the elastic radial inward displacements, and sometimes it is called β to correct for the fact that the indenter shape is not a perfect cone. In reality, these two effects simultaneously coexist and thus it is proposed that this correction factor is α = βγ. From nanoindentation data measured on three materials of different elastic moduli with a sharp Berkovich indenter and a worn one, the tip of which was blunt, it is demonstrated that the correction factor α does not have a constant value for a given material and indenter type but depends on the indenter tip rounding and also on the deformation of the indenter during indentation. It seems that α increases with the tip radius and also with the elastic modulus of the measured materials.

Type
Articles
Copyright
Copyright © Materials Research Society 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Oliver, W.C. and Pharr, G.M.: An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 564 (1992).Google Scholar
2.Martin, M. and Troyon, M.: Fundamental relations used in nanoindentation: Critical examination based on experimental measurements. J. Mater. Res. 17, 2227 (2002).Google Scholar
3.Pharr, G.M., Oliver, W.C. and Brotzen, F.R.: On the generality of the relationship among contact stiffness, contact area, and elastic modulus during indentation. J. Mater. Res. 7, 613 (1992).CrossRefGoogle Scholar
4.King, R.B.: Elastic analysis of some punch problems for a layered medium. Int. J. Solids Structures 23, 1657 (1987).CrossRefGoogle Scholar
5.Hay, J.C., Bolshakov, A. and Pharr, G.M.: A critical examination of the fundamental relations used in the analysis of nanoindentation data. J. Mater. Res. 14, 2296 (1999).CrossRefGoogle Scholar
6.Cheng, Y-T. and Cheng, C-M.: Further analysis of indentation loading curves: Effects of tip rounding on mechanical property measurements. J. Mater. Res. 13, 1059 (1998).Google Scholar
7.Troyon, M. and Martin, M.: A critical examination of the P-h2 relationship in nanoindentation. Appl. Phys. Lett. 83, 863 (2003).CrossRefGoogle Scholar
8.Gong, J., Miao, H. and Peng, Z.: On the contact area for nanoindentation tests with Berkovich indenter: Case study on soda-lime glass. Mater. Lett. 58, 1349 (2004).Google Scholar
9.Shih, C.W., Yang, M. and Li, J.C.M.: Effect of tip radius on nanoindentation. J. Mater. Res. 6, 2623 (1991).Google Scholar
10.Lim, Y.Y. and Chaudhri, M.M.: Experimental investigations of the normal loading of elastic spherical and conical indenters on to elastic flats. Philos. Mag. 83, 3427 (2003).Google Scholar
11.Chaudhri, M.M.: A note on a common mistake in the analysis of nanoindentation data. J. Mater. Res. 16, 336 (2001).CrossRefGoogle Scholar
12.Bolshakov, A. and Pharr, G.M.: Influences of pile-up on the measurement of mechanical properties by load and depth-sensing indentation techniques. J. Mater. Res. 13, 1049 (1998).CrossRefGoogle Scholar