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Validity of the reduced modulus concept to describe indentation loading response for elastoplastic materials with sharp indenters

Published online by Cambridge University Press:  31 January 2011

In-suk Choi*
Affiliation:
Forschungszentrum Karlsruhe, Institute for Materials Research II, 76344 Karlsruhe, Germany
Oliver Kraft and Ruth Schwaiger
Affiliation:
Forschungszentrum Karlsruhe, Institute for Materials Research II, 76344 Karlsruhe, Germany; and Universität Karlsruhe, Institut für Zuverlässigkeit von Bauteilen und Systemen, 76131 Karlsruhe, Germany
*
a) Address all correspondence to this author. e-mail:[email protected]
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Abstract

Recent computational parametric studies have developed reverse algorithms to extract material properties of elastoplastic materials using experimental sharp nanoindentation. These methods used reduced modulus in their parameters to include the effect of indenter compliance. To investigate the validity of using reduced modulus, we conducted experimental indentation of a couple of representative cases for elastoplastic metals with a diamond and a sapphire Berkovich tip. Then, we performed a finite element study for sharp indentation of the same material systems. Both computational and experimental results indicate that the use of reduced modulus is invalid to describe indentation loading response for elastoplastic materials in a certain material regime. Our results show that indenter compliance is overestimated by the previous predictions using reduced modulus. This overestimation leads to underestimation of indenter curvature and causes error in extracting material properties by reverse algorithms.

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Copyright
Copyright © Materials Research Society 2009

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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, 1564 (1992).CrossRefGoogle Scholar
2.Chaudhri, M.M.: A note on a common mistake in the analysis of nanoindentation data. J. Mater. Res. 16, 336 (2001).CrossRefGoogle Scholar
3.Lim, Y.Y. and Chaudhri, M.M.: Indentation of elastic solids with rigid cones. Philos. Mag. 84, 2877 (2004).CrossRefGoogle Scholar
4.Cao, Y.P., Dao, M., and Lu, J.: A precise correcting method for the study of the superhard material using nanoindentation tests. J. Mater. Res. 22, 1255 (2007).CrossRefGoogle Scholar
5.Bucaille, J.L., Stauss, S., Felder, E., and Michler, J.: Determination of plastic properties of metals by instrumented indentation using different sharp indenters. Acta Mater. 51, 1663 (2003).CrossRefGoogle Scholar
6.Chollacoop, N., Dao, M., and Suresh, S.: Depth-sensing instrumented indentation with dual sharp indenters. Acta Mater. 51, 3713 (2003).CrossRefGoogle Scholar
7.Cao, Y.P. and Lu, J.: A new scheme for computational modeling of conical indentation in plastically graded materials., J. Mater. Res. 19, 1703 (2004).CrossRefGoogle Scholar
8.Cao, Y.P., Qian, X.Q., Lu, J., and Yao, Z.H.: An energy-based method to extract plastic properties of metal materials from conical indentation tests., J. Mater. Res. 20, 1194 (2005).CrossRefGoogle Scholar
9.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
10.Huber, N., Tyulyukovskiy, E., and Kraft, O.: On the analysis of the stress-strain behaviour of thin metal films on substrates using nanoindentation. Philos. Mag. 86, 5505 (2006).CrossRefGoogle Scholar
11.Wang, L.G. and Rokhlin, S.I.: Universal scaling functions for continuous stiffness nanoindentation with sharp indenters. Int. J. Solids Struct. 42, 3807 (2005).CrossRefGoogle Scholar
12.Cao, Y.P., Qian, X.Q., and Huber, N.: Spherical indentation into elastoplastic materials: Indentation-response based definitions of the representative strain. Mater. Sci. Emg. A, 454, 1 (2007).Google Scholar
13.Watanabe, M., Mercer, C., Levi, C.G., and Evans, A.G.: A probe for the high temperature deformation of thermal barrier oxides. Acta Mater. 52, 1479 (2004).CrossRefGoogle Scholar
14.Sawant, A. and Tin, S.: High temperature nanoindentation of a Re-bearing single crystal Ni-base superalloy. J. Biomech. 58, 275 (2008).Google Scholar
15.Neumann, P.: Simplification of crystallographic calculations in hexagonal lattices through consequent application of 4-axis hexagonal coordinate system. Phys. Status Solidi 17, K71 (1966).Google Scholar
16.Tavassoli, A-A.F., Rensman, J-W., Schirra, M., and Shiba, K.: Materials design data for reduced activation martensitic steel type F82H. Fusion Em. Des. 61–62, 617 (2002).CrossRefGoogle Scholar
17. Matweb. www.matweb.com. (Automation Creation, Inc., 2008).Google Scholar
18.Aktaa, J.: Private communication. (2008).Google Scholar
19.Choi, I.S., Dao, M., and Suresh, S.: Mechanics of indentation of plastically graded materials—I: Analys is. J. Mech. Phys. Solids 56, 157 (2008).CrossRefGoogle Scholar
20.Choi, I.S., Detor, A.J., Schwaiger, R., Dao, M., Schuh, C.A., and Suresh, S.: Mechanics of indentation of plastically graded materials—II: Experiments on nanocrystalline alloys with grain size gradients. J. Mech. Phys. Solids 56, 172 (2008).CrossRefGoogle Scholar