Study on the influence of outer liner material on the formation and penetration behavior of coated explosively formed projectile

The formation mechanism of the coated explosively formed projectile is revealed, which mainly includes the double liner impact stage, the radial coating closing stage and the metal precursor penetrator stretching stage. The results of mechanism analysis show that the edge of the variable thickness outer liner near the explosive is thinner, resulting in the impact collapse velocity of the edge is higher than that of the center, and the outer liner closes forward and collides with the sub-diameter reactive liner, thus forming a metal precursor penetrator with the outer liner as the main body and a large-diameter projectile with the reactive material. When the outer liner material is replaced with copper, steel, titanium and aluminum in turn, the tip velocity of the coated explosively formed projectile increases, the metal precursor penetrator and the trailing coated projectile can be formed. The penetration of steel target by coated explosively formed projectile is studied, the simulation shows that the penetration of steel target by coated explosively formed projectile with copper outer liner is about 1.50 CD (charge diameter), and the main penetration process concludes the hole opening of the metal precursor penetrator and the expansion with the entry of the trailing coated projectile. When the liner material is replaced with copper, steel, titanium and aluminum in turn, the density of the liner material reduces, the tip velocity of the coated explosively formed projectile increases, and the penetration depth of the steel target reduces.