Metal foams are a relatively new class of light-weight cellular materials with moderate stiffness and strength, which can be used in many applications as the core of sandwich structures -, aerospace, transportation, and biomedical industries.This study utilized a commercial c1osed-ce1l aluminium foam (ALPORAS), and sandwich panels fabricated with ALPORAS cores and skins of aluminium alloys of high and low yield strength.The mechanical properties of the aluminium foam were found through indentation tests. It was realized that the shear strength is obtained only through shallow indentations. and the tear energy is obtained through deep indentations; therefore, thinner panels are not suitable to determine the tear energy. Models were developed to determine the indentation load and mechanical energy absorption of the foam-only panels.Both quasi-static and impact indentations were performed on sandwich panels. Panels of high yield strength skins showed higher load capacity but lower energy absorption, prior to skin failure. Also, the load bearing and energy absorption were higher in impact indentation. Generally, the core thickness did not affect the load bearing and energy absorption, but larger indenters induced higher load bearing and energy absorption. A model was developed to determine the load bearing of the panels with high strength skins, when they were subjected to quasi-static indentation with small hemispherical Indenters.The bending response of the panels was studied under three-point bending and four-point bending loading. Various types of failure modes were observed in the sandwich panels, depending on the testing configuration, skin type and core density: indentation, core yielding, face yielding, core shearing and a combination of them. The failure loads increased with the increasing yield strength of the skin, and their prediction was in good agreement with the developed models.The bending response of sandwich panels, locally damaged by hemispherical indenters, was also investigated when the local damage was located on the tensile/compression side of the panels. It was concluded that the location and size of the local damage did not have a considerable Influence on the resistance of the panels.
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