Hardness mapping assessments and ammunition performance of different metallic projectiles for high velocity impact applications

Depth of penetration (DOP) studies are useful for understanding projectile perforation characteristics under high-velocity impact conditions in the context of armor design and development. DOP is influenced by various parameters, such as projectile mass, hardness, size, and nose shape. Conducting DOP experiments is time-consuming and labor-intensive. To address these challenges, projectiles of 9 × 19 mm, 7.62 × 51 mm (M80), and 5.56 × 45 mm (M855) were used in experimental DOP analysis. These projectiles were selected to represent threat levels from handguns to rifles, consistent with the National Institute of Justice (NIJ) Standard 0101.07. Initially, tensile tests were conducted on the aluminum target material using three-dimensional digital image correlation (3D-DIC). Material hardness mapping was also performed to characterize the constituent parts of the projectiles. Subsequently, high velocity impact tests were conducted using a single-stage gas gun, and projectile motion was captured with high-speed cameras. The samples tested were then evaluated using X-ray imaging to measure DOP. Following the impact tests, finite element (FE) models were developed and validated against experimental results. The numerical simulations showed good agreement with the experimental data, with DOP deviations of less than 1.8% and 11% for the 5.56 × 45 mm and 7.62 × 51 mm projectiles, respectively. The findings contribute to a better understanding of ammunition performance under high velocity impact.