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The Strain Gradient Effects in Micro-Indentation Hardness Experiments

Published online by Cambridge University Press:  10 February 2011

Z. Xue ,
Y. Huang ,
H. Gao  and
W.D. Nix
Z. Xue
Affiliation:
Dept. of Mechanical & Industrial Eng., Univ. of Illinois, Urbana, IL 61801
Y. Huang
Affiliation:
Dept. of Mechanical & Industrial Eng., Univ. of Illinois, Urbana, IL 61801
H. Gao
Affiliation:
Division of Mechanics and Computation, Stanford University, Stanford, CA 94305
W.D. Nix
Affiliation:
Dept. of Materials Science and Engineering, Stanford University, Stanford, CA 94305
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Abstract

Micro-indentation experiments have shown very strong size dependence of the indentation hardness, a phenomenon that cannot be explained by classical plasticity theories. A theory of mechanism-based strain gradient (MSG) plasticity has been developed based on the Taylor model in dislocation theories, and is intended for materials and structures whose dimension controlling plastic deformation falls roughly between 0.1 to 10 microns. The MSG plasticity theory is used in the present study to investigate the size effects observed in micro-indentation experiments. It is shown that the theory can indeed reproduce micro-indentation experimental data, thus providing an important self-consistent check of the MSG plasticity theory.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 578: Symposia A/C – Multiscale Phenomena in Materials - Experiments in Modeling , 1999 , 53
Copyright
Copyright © Materials Research Society 2000

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References

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