Influence of Glass Cenosphere Wall‐Thickness‐to‐Radius Ratio on Compressive Deformation and Damage Behavior of Aluminum Matrix Syntactic Foams

Aluminum matrix syntactic foams (AMSFs) containing glass cenospheres (GCs) with different wall‐thickness‐to‐radius ratios ( t/R ) were prepared while maintaining comparable density and porosity. The influence of GCs t/R on deformation behavior, postpeak softening, and energy absorption of AMSFs was systematically investigated under quasistatic compression, and further correlated with the bending performance of sandwich panels employing AMSFs as the core layer. The results show that increasing t/R leads to an increase in peak strength, accompanied by a change in postpeak deformation behavior. Low‐ t/R AMSFs exhibit smooth stress reduction and delayed strain localization, whereas high‐ t/R AMSFs display abrupt stress drops associated with the rapid formation of concentrated shear bands near peak stress. Although energy absorption is dominated by postpeak deformation in all AMSFs, increasing t/R progressively shifts a larger fraction of energy dissipation toward the peak‐stress regime, reflecting earlier and more localized damage evolution. The bending performance of sandwich panels directly reflects the compressive damage characteristics of AMSF cores, establishing a clear correspondence between material‐level strain localization behavior and structural performance. These findings indicate that the GCs t/R provides an effective parameter for compressive strength, softening characteristics, and energy absorption in AMSFs, offering guidance for the design of lightweight sandwich structures.