Some Features of Fragmentation of an Aluminum Projectile at Various Velocities of Penetration into a Mesh Bumper
T. A. Shumikhin1, P. N. Kalmykov2, N. V. Lapichev2, A. I. Leont'ev2, D. E. Martyushov2, N. N. Myagkov1, V. N. Nomakonova2, A. V. Sal'nikov2, L. N. Bezrukov3
1Institute of Applied Mechanics, Russian Academy of Sciences, Moscow, 123040, Russia
2RFNC, All-Russian Research Institute of Experimental Physics, Sarov, 607188, Russia
3State Research Institute of Aviation Systems, Moscow, 125319, Russia
Keywords: high-velocity impact, fragmentation, mesh bumper, screen protection
Abstract
The fragmentation of projectiles penetrating into thin discrete bumpers is accompanied by ejections of material from the front part of the projectile in the direction of its movement. Material ejection from the front part of the projectile and fragments of the rear part of the projectile form two groups of fragments. The distribution of craters formed by these groups of fragments was analyzed, and the intensity and nature of the damage they caused and the effect of projectile velocity on the kinetic energy distribution between these groups were determined. Fragments were recorded using witness plates of great thicknesses placed at a certain distance behind the steel mesh bumper on the path of movement of fragments. It was found that with an increase in velocity, the proportion of specific kinetic energy of the front ejections increased and the fraction of the kinetic energy of the fragments of the rear of the projectile decreased. The kinetic energy distribution was determined in the case of fragmentation of a projectile of an aluminum alloy of 9 mm diameter on a tungsten mesh (wire diameter 0.5 mm, aperture 3.2 mm). The diameter of the projectile to the cell size of the tungsten mesh was the same as for steel mesh. Significant difference shown The kinetic energy distributions for the tungsten and steel mesh were found to be significantly different, probably due to the strength characteristics of the projectile material and the smaller wire diameter in experiments with the tungsten mesh. The features of damage to the witness plate by a group of small fragments were analyzed.
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