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Texas Tech University, H. S. Tanvir Ahmed, December 2010
CHAPTER 1
TENSILE TESTING OF NANOMATERIALS
1.1 Introduction
Porous materials have a combination of mechanical properties that make them
attractive for many engineering applications. They are lightweight, have a capacity to
undergo large deformation without generation of localized damaging peak stresses,
and possess high surface area per unit volume [1]. Porous metal membranes may be
considered as ideal candidates [2] for lightweight-structural sandwich panels, energy
absorption devices, and heat sinks. The use of porous metal coatings is ever increasing
in renewable-energy system applications [3] as solar cells and hydrogen fuel cells.
Recent researches on nanoporous materials are suggestive of their future uses as
electrochemical [4] or chemical [5] actuation, tunable conductors [6, 7] and magnets
[8, 9]. In particular, the scale of porosity in metal coatings is particularly important to
their catalytic performance [10]. Potentially just as important is the mechanical
stability of the porous coating in these devices. Thus, understanding the mechanical
behavior of these foams in a wide range of strain rates is important for such potential
applications, where the rate of deformation may originate as rapid thermal stress-strain
cycles.
Use of compression testing and nanoindentation to reveal mechanical
properties of porous materials is been reported by many researchers [2, 11, 12, 13, 14,
15, 16, 17, 18]. In this study, a series of rate-dependent tensile tests are conducted to
better understand the operative deformation mechanisms in the evaluation of strength
as the scale of the porous structure changes from the micro-to-nano regime.
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