Energy absorption during projectile perforation of thin steel plates and the kinetic energy of ejected fragments

Abstract

This paper concerns energy absorption in thin (0.4 mm) steel plates during perforation by spherical projectiles of hardened steel, at impact velocities between 200 and 600 m s -1 . Absorbed energies have been obtained from measured incident and emergent projectile velocities. These tests were simulated using ABAQUS/Explicit, using the Johnson and Cook plasticity model. Astrain rate-dependent, critical plastic strain fracture criterion was employed to model fracture.Good agreement is obtained between simulations and experiment and the model successfully captures the transitions in failure mode as projectile velocity increases. At velocities close to the ballistic limit, the plates fail by dishing and discing. As the incident velocity is increased, there are two transitions in failure mode, firstly to shear plugging and secondly to fragmentation and petalling. The simulations also show that, during the latter mode of failure, the kinetic energy of ejected debris is significant, and failure to include this contribution in the energy balance leads to a substantial over-estimate of the energy absorbed within the sheet. Information is also presented relating to the strain rates at which plastic deformation occurs within the sample under different conditions. These range up to about 10 5 s -1 , with the corresponding strain rate hardening effect being quite substantial (factor of 2-3 increase in stress).

Behaviour of uniaxially preloaded aluminium plates subjected to high-velocity impact

“…The failure modes depend on the projectile, material, thickness and impact velocity. Dishing could result at impact velocities slightly higher than the ballistic limit, and a transition from shear plugging to petalling and fragmentation could occur at higher-impact velocities as demonstrated by Dean et al (2009).…”

Effect of Periphery Fixity on Ballistic Limit of Thin Aluminum Plate Subjected to Blunt and Ogival Projectile Impact

“…The failure mode of target struck by a blunt nosed projectile (Børvik et al, 2001;2002;Gupta et al, 2006;Arias et al, 2008;Børvik et al, 2009;Dean et al, 2009), hemispherical projectile (Børvik et al, 2002;Gupta et al, 2006; and ogive nosed projectile (Gupta et al, 2007;2010a;2012) has been investigated.…”

“…The experimental results are finally compared to similar experiments on steel and concrete targets, and the capacity of the different materials is evaluated in relation to total weight. Dean et al (2009) studied the impact phenomenon of thin (0.4mm) steel plates impacted by spherical projectiles of hardened steel. At velocities close to the ballistic limit, the plates fail by dishing and discing.…”

Experimental investigations on the ballistic impact performances of cold rolled sheet metals

“…The Rusinek-Klepaczko model was shown to be in good agreement with experimental results. Dean et al [10] modeled the absorbed impact energies of the steel plates using Johnson-Cook plasticity algorithm.…”