Comparative study of effect of fragment nose shapes on damage characteristics of thin target plate in ballistic applications

Abstract

Experimental and numerical investigations in ballistic applications have predominantly focused on determining the ballistic limit of target plates for various projectile shapes. However, limited attention has been given to the influence of projectile nose shapes at high impact velocities. To address this gap, 3D FE simulations were carried out on a 1 mm thin target plate using J-C material model, the Gruneisen equation of state (EOS), an erosion contact algorithm, and the explicit FE code LS-DYNA. The simulations involved impact of fragments of equal mass but different nose shapes. The results revealed a significant influence of fragment shape on both the ballistic limit and overall plastic deformation of the target plate. Particularly, the target plate impacted by a hexagonal pyramid fragment shape exhibited the highest ballistic limit and global plastic deformation. Further, it was also observed that at higher impact velocities, the former fragment shape caused the maximum damage to the target plate, while at lower impact velocities, the cubical fragment shape demonstrated the highest lethality. This difference in target damage is known to be governed by the energy required to erode the target and fragment material. The results from the current study offers valuable insights into how different fragment shapes influence the damage inflicted on target plates in ballistic scenarios. The findings presented in this study also offer guidance on selecting suitable fragment shapes for future use in Fragment Generator Warheads (FGW) in order to maximize the damage or lethality inflicted on targets.