Citation:
Abstract:
Foam-based composites are advanced materials that combine lightweight design with high mechanical strength and stiffness, making them attractive for diverse engineering applications. Their mechanical performance is strongly influenced by foam morphology, including strut geometry in open-cell foams and cell wall topology in closed-cell foams. This study investigates the effect of these morphological features on the mechanical behavior of foam-based composites, considering both open-cell and closed-cell foams as matrix phases. A finite element-based numerical homogenization approach evaluates mechanical performance over a wide range of phase volume fractions and stiffness contrasts. The results reveal significant differences in stress distribution, load transfer efficiency, and overall mechanical response between the two foam morphologies. Open-cell foam composites, particularly those with cylindrical struts, show superior load-bearing capacity under high stiffness contrast. In contrast, closed-cell composites develop stress localization unless optimized with thin walls and dense reinforcement. The findings indicate that the mechanical efficiency is governed by three main factors: (i) phase stiffness contrast, determining how morphology affects performance; (ii) phase connectivity or interpenetration, controlling stress transfer through the stiff phase; and (iii) strut geometry, where rounded struts aligned with the load enable direct stress transfer while minimizing matrix deformation.