Experimental analysis of energy absorption characteristics in composite sandwich structures with 3D-printed honeycomb core under quasi-static compression

The demand for lightweight, high energy-absorbing structures in engineering applications necessitates the development of advanced materials and manufacturing techniques. Composite sandwich structures, with their excellent strength-to-weight ratios and energy dissipation properties, offer promising solutions. This study investigates the energy absorption characteristics of composite sandwich structures with 3D-printed honeycomb core. The skin was fabricated through hand lay-up techniques with carbon and glass fibers and honeycomb core fabricated from polylactic acid by fused deposition modeling. Quasi-static compression testing and optical analysis evaluated energy absorption ( E a ), specific energy absorption ( SEA ), and crush force efficiency ( CFE ). Sandwich structures with vertical cores exhibited superior energy dissipation due to enhanced stability and resistance to buckling. Also, sandwich structures with carbon fiber skins achieved the highest SEA and E a values, demonstrating improved energy absorption prior to densification. Horizontal cores, despite lower SEA , provided stable crushing behavior, supporting consistent load distribution. Core crushing with plastic deformation was identified as the primary failure mechanism. The results highlight the significant influence of structural orientation and material selection on energy absorption performance. Sandwich structures with vertically oriented cores and carbon fiber-reinforced skins showed the greatest potential for high-energy absorption applications, offering a cost-effective and efficient solution for advanced engineering needs.