Modelling of Armour-piercing Projectile Perforation of Thick Aluminium Plates

This study investigates the perforation process of armour-piercing projectiles on commercially available high-strength aluminium. A LS-DYNA® model is developed with thick target plates of aluminium alloy 7075-T651 and an incoming 7.62 mm armour-piercing projectile with an impact velocity of 850 m/s. A numerical formulation combining classic Lagrangian finite elements with an adaptive mesh algorithm is utilized to overcome large deformation challenges and more accurately predict failure mechanisms. Both aluminium target and projectile have been modelled as deformable with a modified version of the Johnson-Cook strain-rate and temperature dependent plasticity model, based on input parameters from literature. Main model results include projectile residual velocity after target perforation and prediction of target failure mechanism. The model results are validated against experimental results from live ballistic tests and a sensitivity study is carried out to identify influential material model parameters.