INSTRUMENTATION AND EXPERIMENTATION - Nanoindentation with Biological Applications - page 38

CHAPTER 3
INSTRUMENTATION AND EXPERIMENTATION
Krystyn J. Van Vliet
Department of Materials Science and Engineering,
Department of Biological Engineering,
Massachussets Institute of Technology
E-mail: [e-mail]
In this chapter, practical experimental issues associated with
the mechanical testing of biological materials are considered.
Nanoindenters and atomic force microscope devices are considered
in separate sections, with best practice recommendations for testing
materials of different stiffnesses in each configuration. Technical
aspects of commercial instrumentation are examined, including load
and displacement resolution, load and displacement ranges, stability of
the instrument signals and compliance of the load-frame. Significant
emphasis is placed on mechanisms for achieving environmental control
necessary for biological materials testing, including temperature and
humidity effects, specimen preparation and stability of the biological
samples themselves.
1. Introduction
There are several differences between the experimental set-ups for
instrumented indentation (sometimes termed 'nanoindentation') and
atomic force microscope (AFM)-enabled indentation, as discussed at
length in Chapter 2 . There are therefore slightly different experimental
considerations for the two types of testing, and one or the other technique
may be more suited for the experiment being planned. There are also
differences based on material class, especially related to material
stiffness. A summary of experimental design variables for a range of
materials (with different stiffnesses) is presented in Table 3-1 ; in the
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