Evaluation of energy absorbing materials under blast loading

Abstract

Traditional blast protection systems present a hard metallic surface, which acts to deflect and attenuate the blast loading. However, more recently, lightweight energy absorbing materials, including cellular materials, are being considered. These materials reduce the transmitted force by deforming elastically or plastically under the blast load. In this study, four commercially available energy absorbing materials were considered for application in blast protection. The materials considered were aluminium foam, Nomex ® honeycomb, Skydex ® and expanded polystyrene. The impulse transmitted by the rear face of experimental test panels under blast loading was assessed by positioning a mass on the rear face of each of the four panels, the velocity of which was measured using high speed imaging. Measurements of the permanent deformation of the rear face of the panels were also taken. The aluminium foam recorded both the lowest permanent deformation and impulse transfer to the mass of the materials tested, making it the most suitable material of those tested for use as an appliqué panel in this particular scenario. Analysis of the panels suggested that for the particular experimental setup used, minimal energy was absorbed by plastic deformation or crushing of the energy absorbing materials. Instead, the permanent deformation of the panels may be related to the mechanical properties of the materials in the plane perpendicular to the blast load.

Bioinspired cementitious-polymer composite for increased energy absorption

“…Given the increased deformation and the potential for increased energy absorption capacity, one potential application of this composite is for civil infrastructure designed for high strain rate or dynamic events [20][21][22]. The enhanced energy absorption could feasibly yield greater fatigue resistance and improved resiliency.…”

Effect of Reinforcement in Energy Absorption Characteristics of Honeycomb Structures Under Blast Loading

“…Dharmasena et al performed explosive test to study mechanical properties of honeycomb sandwich panel and solid plate having equal areal density [5]. There exist several researches on the energy absorption characteristics of sandwich panel composites [6][7][8][9][10]. The core structure attenuates the velocity, thereby reducing the deflection at the back face of the sandwich composite [11].…”

Testing the blast response of foam inserts for helmets

“…In open cell polyurethane foams of the type seen in combat helmets, the collapse mechanism is elastic buckling. Cell collapse ends once opposing cell walls begin to touch, and structure densifies with stiffness increasing rapidly [ 27 ]. This is the point of densification, where further force compresses the material itself [ 27 , 28 ].…”

“…Cell collapse ends once opposing cell walls begin to touch, and structure densifies with stiffness increasing rapidly [ 27 ]. This is the point of densification, where further force compresses the material itself [ 27 , 28 ]. Foam deformation in response to loading is not uniform, as it first occurs in the weakest point of the material, which cannot be predicted due to the random nature of bubble formation during manufacture [ 29 ].…”