Research on interfacial toughness of laser‐induced graphene and short <scp>K</scp>evlar fibers aramid fiber/foam aluminum sandwich structure

Abstract The interface performance of the aramid fiber/foam aluminum sandwich structure is poor due to the lack of fiber connections between the core and face sheets, negatively impacting overall load‐bearing capacity. This study investigates the effects of laser‐induced graphene (LIG) and short Kevlar fibers on the interfacial toughness of aramid fiber/foam aluminum sandwich panels, aiming to enhance the interfacial bonding capability of the structure. Results demonstrate that the synergistic toughening effect of LIG and short Kevlar fibers significantly improves the interlaminar toughness, with a 134.90% increase in peak load and a 161.64% increase in energy absorption during the three‐point bending tests. Scanning electron microscopy (SEM) analysis reveals the toughening mechanism: the micro‐porous structure of LIG provides effective adhesion points for the short Kevlar fibers, creating a stable fiber bridging structure that mitigates interface delamination. Furthermore, optimization of the surface density of the short Kevlar fibers for the LIG‐coated aramid fiber/aluminum foam sandwich panels shows a trend of increasing toughness followed by a decline with increasing surface density, with optimal interfacial performance achieved at a surface density of 6 g/m 2 . These findings suggest that the combined approach of LIG and short Kevlar fibers is an effective strategy for enhancing the interfacial toughness of aramid fiber/foam aluminum sandwich panels, with promising applications in composite materials. Highlights LIG‐Kevlar fibers improve toughness &amp; energy absorption in sandwich panels. The optimal short Kevlar fiber density for interfacial performance is 6 g/m 2 . LIG‐Kevlar forms a “bridging structure” to prevent delamination.