Study On The Ballistic Impact Effect Of Sandwich Panels With Aluminum Honeycomb Cores

Due to a series of advantages of light weight, high specific strength, high specificrigidity, and excellent sound and thermal insulation properties, metal sandwich panels withhoneycomb cores have been widely used in aerospace, high-speed trains, constructions andother fields. Many studies show that honeycomb materials have the capacity of dissipatingconsiderable energy by large plastic deformation at nearly constant nominal stress, so it is anew type of anti-shock function material and has been employed in the actual engineering.However, most studies on the mechanical properties of sandwich structures mainly focus onthe quasi-static and low-velocity impact loading condition, and little attention has beengiven to the dynamic response under impact loading.In this research, experimental, computational and analytical investigations wereconducted on a number of clamped square metallic sandwich panels with honeycomb coresunder impact loading. And the dynamic behaviors and energy-absorbing characteristics areanalyzed. Some significant conclusions are drawn.First, a series of ballistic impact tests were carried out on the Φ57mm gas gun system.Effects of several key parameters, i.e. impact velocity, skin thickness, core density andprojectile shapes, were analyzed. The results showed that the aluminum honeycomb corecould improve the ballistic limit of sandwich panels effectively. Moreover, under the sameimpact velocity, the energy absorption was found lower for the flat-nosed projectiles thanthe hemispherical and conical-nosed projectile. Second, the mechanical behavior of thesandwich panels with aluminum honeycomb cores were models with ABAQUS. Thesimulation results were compared with and testified the experiments. The energy dissipationand deformation modes in different part of sandwich panels were obtained. And thesimulation of attact angle penetration resulted that it greatly affected the energy absorption.At last, based on the experiment and simulation, the mechanism of energy absorption ofsandwich panels was analyzed according to the different failure modes caused by noseshapes, and the theoretical model was established. The research results are of worth tooptimum design of sandwich panels.