Dynamic Crushing of All-Metallic Corrugated Panels Filled With Close-Celled Aluminum Foams

Abstract

Under quasi-static uniaxial compression, inserting aluminum foams into the interstices o f a metallic sandwich panel with corrugated core increased significantly both its peak crushing strength and energy absorption per unit mass. This beneficial effect diminished however if the foam relative density was relatively low or the compression velocity became sufficiently high. To provide insight into the varying role o f aluminum foam filler with increasing compression velocity, the crushing response and collapse modes o f all metallic corrugate-cored sandwich panels filled with close-celled aluminum foams were studied using the method o f finite elemen ts (FEs). The constraint that sandwich panels with and without foam filling had the same total weight was enforced. The effects o f plastic hardening and strain rate sensitivity o f the strut material as well as foam!strut interfacial debonding were quantified. Three collapse modes (quasi-static, transition, and shock modes) were identified, corresponding to different ranges o f compression velocity. Strengthening due to foam insertion and inertial stabilization both acted to provide sup port fo r the struts against buckling. At relatively low compression velocities, the struts were mainly strengthened by the surrounding foam; at high compression velocities, inertia stabilization played a more dominant role than foam filling.

Mechanical Stability of Hybrid Corrugated Sandwich Plates under Fluid-Structure-Thermal Coupling for Novel Thermal Protection Systems

“…By element assembling procedure, the global matrices of mass M, structural stiffness K, geometric stiffness K G , aerodynamic stiffness K a , aerodynamic damping C a and the global nodal force vector F T caused by thermal expansion are obtained according to Equations (17), (21), (26), (31) and (28). The total kinetic energy, potential energy and work done by external force are given in terms of the global nodal displacement vector d, as…”

“…Zhang et al discovered the limited enhancement of filling foam in compressive strength and impact resistance due to the relatively weak and low-density foam material [14]. Yan et al [15,16] and Yu et al [17] utilized closed-cell aluminum foam instead of polymeric foam and demonstrated that foam filler effectively improved compressive and bending strength by stabilizing effects on the corrugated members against buckling. Han et al [18] revealed that filling foam contributed to both enhanced buckling resistance and additional mass, and subsequently assessed the structural efficiency through optimization study.…”

Effects of aluminum foam filling on the low-velocity impact response of sandwich panels with corrugated cores

“…A constant velocity V was imposed on the front face sheet so that the core was uniaxially compressed. Much more modeling details can be seen in our previous study [8,46].…”

Impact response of a sandwich with a foam aluminum core enhanced by a ceramic tile: An experimental study

“…To improve the mechanical performance of a porous core, like its load-bearing capacity and impact resistance, researchers have assessed, experimentally and analytically, several approaches. These can be classified as follows: (1) improving the inherent properties of the core by changing its configuration 5,6 or by using a graded design for the parent materials of the core [7][8] or (2) adding a stiffener, like a thin-walled metal grid [9][10] or a tubular stiffener. [11][12] Experimental results show that the load-bearing capacity and energy absorption of a hybrid core composed of a foam core and a thin-walled grid significantly exceed the sum of the two separate components.…”