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Cellular materials are known to be useful in the application of designing light but stiff structures. This applies to
various components used in various industries such as rotorcraft blades, car bodies or portable electronic devices.
Structural application of the metal foam is typically confined to light weight sandwich panels, made up of thin solid
face sheets and a metallic foam core. The resulting high-stiffness structure is lighter than that constructed only out
of the solid metal material. The face sheets carry the applied in-plane and bending loads and the role of the foam
core is separate the face sheets to carry some of the shear stresses, while remaining integral with the face sheet.
Many challenges relating to the fabrication and testing of these metal foam panels continue to exist due to some
mechanical properties falling short of their theoretical potential. Hence in this study, a detailed three dimensional
foam structure is generated using series of 2D Computer Tomography (CT) scans, on Haynes 25 metal foam. Series
of the 2D images are utilized to construct a high precision solid model including all the fine details within the metal
foam as detected by the CT scanning technique. Subsequently, a finite element analysis is then performed on an as
fabricated metal foam microstructures to evaluate the foam structural durability and behavior under tensile and
compressive loading conditions. The analysis includes a progressive failure analysis (PFA) using GENOA code to
further assess the damage initiation, propagation, and failure. The open cell metal foam material is a cobalt-nickel-chromium-tungsten alloy that combines excellent high-temperature strength with good resistance to oxidizing
environments up to 1800 °F (980 °C) for prolonged exposures. The foam is formed by a powder metallurgy process
with an approximate 100 pores per inch (PPI).
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