Experimental and Numerical Investigation of High Velocity Response of Aramid Honeycomb Core Sandwich Structure

In this research, an experimental and numerical analysis of a flat sandwich structure with an aramid honeycomb core using a cylindrical steel ogive-shaped projectile was performed to study the impact resistance of the structure. The flat structure consists of a circular aramid honeycomb core of 200 mm in diameter, having a cell size ranging from 3.2 to 9.2 mm and a 20 mm thickness, backed by circular aluminum alloy facesheets with varying thicknesses from 0.7 to 2 mm on both sides. Models of sandwich structures with honeycomb cores and aluminum skins were built in three dimensions using ABAQUS/Explicit. The numerical analysis has also been expanded to include the impact of core and facesheet geometries, on the energy absorption properties of sandwich structures. In terms of energy absorption, a positive relationship was identified between cell wall thickness and facesheet thickness. In contrast, the cell length negatively impacted the structure’s energy absorption for the ogive projectile. The investigation revealed that with an increase in facesheet thickness from 0.7 to 2 mm, the ballistic limit increased progressively by 23.04, 26.81, and 26.83%, respectively. Conversely, as the cell length increased incrementally from 3.2 to 9.2 mm, the ballistic limit decreased by 3.79, 4.83, and 6.28%, respectively. Similarly, with an increase in cell wall thickness from 0.03 to 0.09 mm, the ballistic limit increased by 4.48, 1.47, and 2.9%, respectively.