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The Role of Indentation Depth on the Measured Hardness of Materials

  • Melissa Shell De Guzman (a1), Gabi Neubauer (a1), Paul Flinn (a1) and William D. Nix (a2)

Abstract

Ultra micro-indentation tests on Ni and Cu samples showed increasing hardness with decreasing penetration depth over a range from 200 to 2000 nm. The results suggest increased strain hardening with decreased indentation depth. To establish that this is a real material effect, a series of tests were conducted on amorphous materials, for which strain hardening is not expected. The hardness of Metglas® was found to be independent of depth. A simple model of the dislocation densities produced under the indenter tip describes the data well. The model is based on the fact that the high density of dislocations expected under a shallow indentation would cause an increase in measured hardness. At large depths, the density of geometrically necessary dislocations is sufficiently small to have little effect on hardness, and the measured hardness approaches the intrinsic hardness of the material.

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1 Burnett, P.J. and Rickerby, D.S., Thin Solid Films 148, 51 (1987).
2 Bhushan, B., Williams, V.S., and Shack, R.V., J. Tribology 110, 563 (1988)
3 Upit, G.P. and Varchenya, S.A., in The Science of Hardness Testing and its Research Applications, edited by Westbrook, J.H. and Conrad, H. (American Society for Metals, 1971) pp. 135146.
4 Stelmashenko, N.A., Walls, M.G., Brown, L.M., and Milman, Y.V., in Mechanical Properties and Deformation Behaviorof Materials Having Ultra-Fine Microstructures. edited by Nastasi, M., Parkin, D.M. and Gleiter, H. (NATO ASI Series E 233,1993) pp. 605610.
5 Taylor, G.I., Proc. Roy. Soc. (London), A145, 362 (1934).
6 Cottrell, A.H., in An Introduction to Metallurgy. (Edward Arnold Publishers Ltd., London 1967), p. 434.
7 Bowden, F.P. and Tabor, D., in The Friction and Lubrication of Solids. (Clarendon Press, Oxford, 1986), p. 12.
8 Doerner, M.F. and Nix, W.D., J. Mater. Res. 6, 601 (1986).
9 Oliver, W.C. and Pharr, G.M., J. Mater. Res. 7,1564 (1992).
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MRS Online Proceedings Library (OPL)
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  • EISSN: 1946-4274
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