Effect of projectile nose shape, impact velocity and target thickness on deformation behavior of aluminum plates

Abstract

The present study deals with the experimental and numerical investigations of aluminum target plates impacted by blunt, ogive and hemispherical nosed steel projectiles. The projectiles were normally impacted on the target plates of 0.5, 0.71, 1, 1.5, 2, 2.5 and 3 mm thicknesses at different velocities with the help of a pneumatic gun. Effect of projectile nose shape, impact velocity and plate thickness on the deformation of the target plates was studied. Hemispherical nosed projectile caused highest global deformation (dishing) of the target plates. Ogive nosed projectiles were found to be the most efficient penetrator for the case of plates of thicknesses 0.5, 0.71, 1.0 and 1.5 mm. For the case of plates of thicknesses 2.0, 2.5 and 3.0 mm however, blunt nosed projectiles required least energy to perforate the target plates. The ballistic limit velocity of hemispherical nosed projectiles was found to be highest as compared to the other two projectiles. Finite element analysis of the problem was carried out using ABAQUS finite element code. Results of the numerical analysis were compared with the experiments and good correlation between the two was found.

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

“…A numerical model was found to be stiffer which causes lower residual velocity compared to experimental results. The experimental and axisymmetric numerical simulation results reported by Gupta et al (2007) 0.0 more significant for blunt nosed projectile impact. Table 4 shows the ballistic limit for ogive as well as blunt nosed projectiles.…”

“…Due to small target thickness frictional effects were not considered between the target and the projectile. The geometry, length (50.8 mm), mass (52.5 grams) and diameter (19 mm) of blunt and ogive nosed projectiles were kept identical to those of the projectiles used by Gupta et al (2007). The target was restrained at its periphery with respect to all degrees of freedom, but the region of clamped periphery was varied as 100%, 75%, 50% and 25%.…”

“…The ballistic limit velocity was found to be higher for hemispherical projectiles than that for blunt projectiles. In extension of the previous study Gupta et al (2007) varied the nose shape of projectile hit on the different target thicknesses. The projectile nose shape was varied as blunt, ogive and hemispherical while the thickness of the aluminum target plate was varied as 0.…”

“…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.…”

“…1mm thick monolithic 1100-H12 aluminum targets of span diameters 255mm with varying boundary conditions were impacted by blunt and ogive nosed projectiles to obtain the ballistic limit. To study the influence of boundary conditions, impact velocities of projectiles were kept identical to those obtained during experiments carried out by Gupta et al (2007). In general, the ballistic limit was found to increase with an increase in unclamped periphery region of target span.…”