Effect of inclusions and holes on the stiffness and strength of 2D cellular solids
Chen C, Lu TJ, Fleck NA.
CUED technical report, CUED/C-MICROMECH/TR.27, June 1999.
A finite element study has been performed on the effects of holes and rigid inclusions on the
elastic modulus and yield strength of a two-dimensional foam under biaxial loading. The focus is
on foams that have already been weakened by a small degree of geometrical imperfection, such as a
random distribution of fractured cell walls, as these imperfect foams resemble those commercially
available. Hashin-Shtrikman lower and upper bounds and self-consistent estimates of elastic moduli
are derived to provide reference solutions to the finite element calculations. It is found that
the strength of an imperfect foam is relatively insensitive to the presence of holes and
inclusions, consistent with recent experimental observations on commercial aluminium alloy