COMPUTATIONAL MODELING OF INDENTATION - Nanoindentation with Biological Applications - page 149

CHAPTER 6
COMPUTATIONAL MODELING OF INDENTATION
Xi Chen
Department of Civil Engineering and Engineering Mechanics,
Columbia University
Email: [e-mail]
Indentation is a popular method for evaluating mechanical properties of
materials and structures, including elastic modulus, yield strength,
hardening coefficient, residual stress, fracture toughness, and viscoelastic
behavior, among others. It can also be applied to measure the properties
of individual phases as well as global properties of composite
materials, coatings and multilayers. Since it requires much less effort
on sample preparation than other techniques, it is in particular useful
for small material structures and biological materials (including living
tissues). The primary challenge remains in the explanation of
indentation data, since the material properties are implicitly related
with indentation response; due to the finite local deformation involved
and nonlinear contact conditions, computation modeling of indentation
is an indispensable tool to correlate the indentation characteristics with
material parameters, from which a reverse analysis can be carried out to
identify material properties from indentation tests.
1. Introduction
Numerous advances in solid mechanics and materials science have been
possible through instrumented indentation, a technique now widely used
to probe mechanical properties of materials. 1 The depth and force of
an indenter penetrating a material are measured continuously over
the complete load cycle, resulting in a force-displacement diagram. Its
popularity arises from that instrumented indentation is easy to conduct,
and that only minor preparation (if any) of the tested material is needed.
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