The role of low-density structural polymeric foams filling the interstices of the cores
of metal sandwich plates is studied to ascertain the strengthening of the cores and
the enhancement of plate performance under crushing and impulsive loads. Square
honeycomb and folded plate steel cores filled with two densities of structural foams
are studied. The foam makes direct contributions to core strength and stiffness, but
its main contribution is in supplying lateral support to core members thereby
enhancing the buckling strength of these members. Performance is assessed at
fixed total weight of the sandwich plate such that the weight of the foam is
traded against that of the metal. The outcome of the comparative study
suggests that plates with foam-filled cores can perform as well, or nearly as
well, as plates of the same weight with unfilled cores. The decision on use of
foams in the cores is therefore likely to rest on multifunctional advantages
such as acoustic and thermal insulation or environmental isolation of core
interstices.
