normal impact; oblique impact; plates; perforation; ricochet
An experimental study of the normal and oblique impact of armour-piercing projectiles on single and layered plates of mild steel, RHA steel and aluminium is presented. The projectiles were fired at an impact velocity of ~800-880 m s -1. The plate thickness varied in the range 4.7--40 mm and the ratio of the plate thickness to the
diameter of the projectile varied in the range 0.75--6.5 for single plates and up to 13 for layered plates. Observations on target damage and measurements of incident and residual velocities and the angles in normal and oblique impact are presented. Determination of plate thickness t*, for which the incident velocity is the ballistic limit, is considered and influences of various parameters, like plate material and its thickness, on t* and the residual velocity are discussed. Relations are developed to determine the residual velocity for a plate of thickness less than t*, and to
relate t* with the hardness of the material. Results for the residual velocity obtained from these relations are compared with those from the experiments.