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Metal foams are expected to find use in structural applications where weight is of particular concern, such as space
vehicles, rotorcraft blades, car bodies or portable electronic devices. The obvious structural application of metal foam is
for light weight sandwich panels, made up of thin solid face sheets and a metallic foam core. The stiffness of the
sandwich structure is increased by separating the two face sheets by a light weight metal foam core. The resulting high-stiffness
structure is lighter than that constructed only out of the solid metal material. Since the face sheets carry the
applied in-plane and bending loads, the sandwich architecture is a viable engineering concept. However, the metal foam
core must resist transverse shear loads and compressive loads while remaining integral with the face sheets. Challenges
relating to the fabrication and testing of these metal foam panels remain due to some mechanical properties falling short
of their theoretical potential. Theoretical mechanical properties are based on an idealized foam microstructure and
assumed cell geometry. But the actual testing is performed on as fabricated foam microstructure. Hence in this study, a
detailed three dimensional foam structure is generated using series of 2D Computer Tomography (CT) scans. The series
of the 2D images are assembled to construct a high precision solid model capturing all the fine details within the metal
foam as detected by the CT scanning technique. Moreover, a finite element analysis is then performed on as fabricated
metal foam microstructures, to calculate the foam mechanical properties with the idealized theory. The metal foam
material is an aerospace grade precipitation hardened 17-4 PH stainless steel with high strength and high toughness.
Tensile and compressive mechanical properties are deduced from the FEA model and compared with the theoretical
values for three different foam densities. The combined NDE/FEA provided insight in the variability of the mechanical
properties compared to idealized theory.
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