Foam-Filled Double-Layer Woven Lattice Truss Sandwich Panels: Manufacturing, Testing and Composite Effects

Woven lattice truss sandwich panel (WLTSP) has excellent debonding resistance, but is limited to the weak core shear performance. To relax the limit of mono-layer thickness and improve the shear rigidity, foam-filled double-layered WLTSPs (FDWLTSPs) were designed and manufactured by vacuum infusion process (VIP), hot-pressing technology (HPT) and filling-foam technique. Flatwise compression and edgewise compression experiments were performed to reveal the composite effects of multi-layered and filling-foam techniques on the mechanical performances of WLTSP. The results show that the strength, stiffness, and energy absorption of FDWLTSPs are significantly improved. The flatwise compression strength of FDWLTSPs is 5.03 MPa, increased by 403%. The edgewise compression strengths of FDWLTSPs with warp-warp, weft-warp, and weft-weft core arrangements, are 21.97 MPa, 24.1 MPa, and 25.63 MPa, increased by 310%, 283%, and 165%, respectively. The failure patterns of coupling of core compression and shear in flatwise compression and those of buckling and face fracture in edgewise compression were revealed.