Experimental and Numerical Investigation of Ballistic Resistance of Polyurea-Coated Aluminum Plates under Projectile Impacts

The effects of the spraying thickness and the position on the response of aluminum plates under impact loading were studied. The impact tests and numerical simulation were conducted for the penetration process of polyurea-coated 2024 aluminum plates with tungsten sphere impacts. The results indicate the impact resistance performance is similar at slower impact velocity (500–1000 m/s), and the front (or double-side) coating has a smaller advantage. When the impact velocity rises to 1500 m/s, the back coating has a better energy-absorbing performance. The polyurea perform more efficiently with the increase in the impact velocity because the elastomer has large-scale deformation. By comparing the different thicknesses of the back coating, the residual velocity of the fragment has small changes and the impact energy absorption increased with the increase in the coating thickness. The separated phenomenon is serious in front of the bonding face with shear compression failure. In the back polyurea layer, the stripping area is smaller than the front bonding face, and the petaloid cracking is formed with tensile failure.