High-speed penetration of ultra-high molecular weight polyethylene plates: Experiments and modeling

High-speed penetration of ultra-high molecular weight polyethylene (UHMWPE) plates is investigated experimentally and numerically. Ballistic tests are conducted on a single stage gas gun with high-speed imaging for spherical projectiles with different diameters (1, 2 and 3 mm) and impact velocities ($\sim$100, 200, 300 and 400 m s⁻¹). Scanning electron micrography on bullet craters reveals multiple deformation and damage modes of UHMWPE, including wearing, shearing, melting, compression and spallation. We develop a constitutive model for UHMWPE based on unaxial compression tests in a wide range of temperatures and strain rates. The finite element method simulations reproduce the experiments, and reveal a linear relation between penetration resistance and instantaneous projectile velocity. A non-dimensional model is proposed to predict the penetration depth for different projectile diameters and impact velocities.