Performance of metallic honeycomb-core sandwich beams under shock loading

Abstract

Stainless steel square honeycomb core sandwich and solid monolithic beams have been subjected to high-pressure, short-duration impulses using a shock simulation technique involving high-speed impact of Al foam projectiles. The experiments have been designed to achieve two objectives: (i) to demonstrate the benefits of sandwich construction, and (ii) to assess the fidelity of dynamic finite element calculations in simulating the structural response. The results affirm that, when subjected to impulse levels representative of those associated with nearby explosions, the sandwich beams exhibit smaller displacements than the solid beams at equivalent weight. The benefit is especially large at lower impulses where the effective dynamic strength of the honeycomb core prevents crushing. The measurements and finite element simulations having greatest relevance to the shock resistance are found to correspond closely, particularly the displacements and the core crushing strains. One implication is that the dynamic finite element model has the requisite fidelity at impulse levels of interest.