Penetration forces on rigid projectiles

AUTODYN simulations have been performed and the retardation force on the rigid projectile has been calculated. Retardation force depending on material strength and material density has been calculated. Different shapes of the projectile front have been investigated. Simulations have been performed of penetration into thick plates and into thin plates, were perforation occur. Different material parameters have been investigated. Simulations show that blunt projectiles with velocities over 1200 m/s can cause hole diameters larger than the projectile, if the target has low strength. It has also been shown that the retardation force depending on target density, sometimes can be relatively large, compared to the retardation force caused by strength. It has also been illustrated that different material parameters have relatively small influence when thick targets are penetrated. Only the yielding stress and the deformation hardening have a large influence. When penetration is made trough thin plates, other material parameters can have influence.