Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-24T01:21:55.535Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of mechanical properties on the contact profile in Berkovich nanoindentation of elastoplastic materials

Published online by Cambridge University Press:  17 November 2011

Jiangting Wang ,
Peter D. Hodgson  and
Chunhui Yang
Jiangting Wang
Affiliation:
Centre for Material and Fibre Innovation, Deakin University, Geelong, Victoria 3220, Australia
Peter D. Hodgson
Affiliation:
Centre for Material and Fibre Innovation, Deakin University, Geelong, Victoria 3220, Australia
Chunhui Yang*
Affiliation:
School of Engineering, Deakin University, Geelong, Victoria 3220, Australia
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

Pile-up or sink-in is always a concern in a nanoindentation test because it gives rise to errors in the estimation of the projected contact area when it is theoretically analyzed with the classic Oliver–Pharr method. In this study, a three-dimensional finite element model is developed to simulate nanoindentation with a perfect Berkovich tip. The variation of the contact profile with respect to the work-hardening rate n and the ratio of yield stress to elastic modulus σy/E has been studied for a wide range of elastoplastic materials. The numerical results show that a low σy/E not only facilitates the pile-up for materials with little or no work-hardening but also enhances the sink-in for materials with a high work-hardening rate. It is attributed to the lateral-flow dominated plastic deformation in low work-hardening materials and the normal-flow dominated plastic deformation in high work-hardening materials, respectively. Because of the large sink-in, for the materials with high n and low σy/E, significant errors in the calculation of the projected contact area can be generated by using the classic Oliver–Pharr method.

Keywords

HardnessNanoindentationSimulation
Type
Articles
Information
Journal of Materials Research , Volume 27 , Issue 1: Focus Issue: Instrumented Indentation , 14 January 2012 , pp. 313 - 319
Copyright
Copyright © Materials Research Society 2011

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.Doerner, M. and Nix, W.: A method for interpreting the data from depth-sensing indentation instruments. J. Mater. Res. 1, 601 (1986).CrossRefGoogle Scholar
2.Oliver, W. and Pharr, G.: Improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564 (1992).CrossRefGoogle Scholar
3.Pharr, G.: Measurement of mechanical properties by ultra-low-load indentation. Mater. Sci. Eng., A 253, 151 (1998).CrossRefGoogle Scholar
4.Bhushan, B. and Li, X.: Nanomechanical characterisation of solid surfaces and thin films. Int. Mater. Rev. 48, 125 (2003).CrossRefGoogle Scholar
5.Oliver, W. and Pharr, G.: Measurement of hardness and elastic modulus by instrumented indentation: Advances in understanding and refinements to methodology. J. Mater. Res. 19, 3 (2004).CrossRefGoogle Scholar
6.Cheng, Y-T. and Cheng, C-M.: Scaling, dimensional analysis, and indentation measurements. Mater. Sci. Eng., R 44, 91 (2004).CrossRefGoogle Scholar
7.Gouldstone, A., Chollacoop, N., Dao, M., Li, J., Minor, A., and Shen, Y.: Indentation across size scales and disciplines: Recent developments in experimentation and modeling. Acta Mater. 55, 4015 (2007).CrossRefGoogle Scholar
8.Tabor, D.: The Hardness of Metals (Clarendon Press, Oxford, 1951).Google Scholar
9.Lim, Y.Y. and Chaudhri, M.M.: The effect of the indenter load on the nanohardness of ductile metals: An experimental study on polycrystalline work-hardened and annealed oxygen-free copper. Philos. Mag. A 79, 2979 (1999).CrossRefGoogle Scholar
10.Bec, S., Tonck, A., Georges, J., Georges, E., and Loubet, J.: Improvements in the indentation method with a surface force apparatus. Philos. Mag. A 74, 1061 (1996).Google Scholar
11.Mata, M. and Alcala, J.: Mechanical property evaluation through sharp indentations in elastoplastic and fully plastic contact regimes. J. Mater. Res. 18, 1705 (2003).CrossRefGoogle Scholar
12.Giannakopoulos, A.E., Larsson, P.L., and Vestergaard, R.: Analysis of Vickers indentation. Int. J. Solids Struct. 31, 2679 (1994).Google Scholar
13.Larsson, P.L., Giannakopoulos, A.E., SÖderlund, E., Rowcliffe, D.J., and Vestergaard, R.: Analysis of Berkovich indentation. Int. J. Solids Struct. 33, 221 (1996).CrossRefGoogle Scholar
14.McElhaney, K., Vlassak, J., and Nix, W.: Determination of indenter tip geometry and indentation contact area for depth-sensing indentation experiments. J. Mater. Res. 13, 1300 (1998).CrossRefGoogle Scholar
15.Bolshakov, A. and Pharr, G.: Influences of pileup on the measurement of mechanical properties by load and depth-sensing indentation techniques. J. Mater. Res. 13, 1049 (1998).CrossRefGoogle Scholar
16.Chen, X. and Vlassak, J.: Numerical study on the measurement of thin film mechanical properties by means of nanoindentation. J. Mater. Res. 16, 2974 (2001).CrossRefGoogle Scholar
17.Dao, M., Chollacoop, N., Van Vliet, K.J., Venkatesh, T.A., and Suresh, S.: Computational modeling of the forward and reverse problems in instrumented sharp indentation. Acta Mater. 49, 3899 (2001).CrossRefGoogle Scholar
18.Taljat, B. and Pharr, G.M.: Development of pile-up during spherical indentation of elastic-plastic solids. Int. J. Solids Struct. 41, 3891 (2004).CrossRefGoogle Scholar
19.Randall, N.: Direct measurement of residual contact area and volume during the nanoindentation of coated materials as an alternative method of calculating hardness. Philos. Mag. A 82, 1883 (2002).CrossRefGoogle Scholar
20.Swaddiwudhipong, S., Hua, J., Tho, K., and Liu, Z.: Equivalency of Berkovich and conical load-indentation curves. Model. Simul. Mater. Sci. Eng. 14, 71 (2006).CrossRefGoogle Scholar
21.Dieter, G.: Mechanical Metallurgy (McGraw-Hill, New York, 1986).Google Scholar
22.Cheng, Y. and Cheng, C.: Relationships between hardness, elastic modulus, and the work of indentation. Appl. Phys. Lett. 73, 614 (1998).CrossRefGoogle Scholar
23.Tsui, T. and Pharr, G.: Substrate effects on nanoindentation mechanical property measurement of soft films on hard substrates. J. Mater. Res. 14, 292 (1999).CrossRefGoogle Scholar
24.Cheng, Y-T.S. and Cheng, C-M.: Effects of ‘sinking in’ and ‘piling up’ on estimating the contact area under load in indentation. Philos. Mag. Lett. 78, 115 (1998).CrossRefGoogle Scholar