Experimental and Numerical Investigations of the Effect of Impact Angle and Impactor Geometry on the High-Velocity Impact Response of Aluminum Honeycomb Structures

In this study, the effects of impact angle and impactor geometry were investigated on the impact behavior of aluminum honeycombs experimentally and numerically. The high-velocity impact tests were carried out using a gas-gun test machine with flat, spherical and conical-head impactors and impact angles of 0°, 15° and 30° at different incident velocities ranging from 55.8 to 150.5 m/s. The numerical models were developed in LS-Dyna finite element code and well validated against the experimental results. The results showed that the impact behavior of honeycombs is considerably dependent on the impactor head geometry and the impact angle. The honeycomb panel impacted by the conical projectile experienced the highest absorbed energy and ballistic limit velocity. Moreover, it was found out that increasing the impact angle increased the absorbed energy and ballistic limit velocity of honeycombs. Furthermore, different impactor head geometries resulted in different failure mechanisms in the course of impact loading.