MECHANICS OF INDENTATION - Nanoindentation with Biological Applications - page 120

CHAPTER 5
MECHANICS OF INDENTATION
Michelle L. Oyen
Department of Engineering, Cambridge University
E-mail: [e-mail]
The fundamental contact mechanics principles underlying nano-
indentation testing techniques are reviewed. A range of material
constitutive responses are covered, including elastic, plastic, and
viscous deformation, and incorporating indentation of linearly
viscoelastic materials and poroelastic materials. Emphasis is on routine
analysis of experimental nanoindentation data, including deconvolution
techniques for material properties measurements during indentation. In
most cases, an analytical approach for an isotropic half-space is
considered. Special cases are briefly described, including anisotropic
materials, inhomogeneous composite materials and layered film-
substrate systems.
1. Introduction
Experimental contact mechanics measurement of material properties
has become extremely popular in the last decade, due to both the
commercialization of dedicated instrumented indentation testing devices
and advances in the practical and experimental understanding of
performing contact mechanics experiments. Many commercial indenters
are set-up as “black-box” instruments for routine mechanical testing,
in which data analysis is automated and “the mechanical properties”
are directly exported from the instrument. However, it is extremely
important to review the underlying contact mechanics that are used in
indentation data analysis for several reasons. First, although an elastic-
plastic analysis (typically based on the method of Oliver and Pharr 1 ) can
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