High entropy alloys (HEAs) have become a significant interest in applications within extreme environments, such as aerospace and defense, due to their unique properties. These unique properties are granted by the compositional complexity and highly-random crystallographic configurations of HEAs. Studies have found that HEAs can often exhibit improved mechanical, electrical, thermal, and chemical properties when compared to conventional alloys, which can be attributed to the tunability of their elemental compositions. Additionally, HEAs often demonstrate unique responses under varying strain rates, displaying strain-rate sensitivity and dynamic strengthening. Understanding, modeling, and predicting the performance of different HEAs in these extreme environments is an ongoing area of research in material science and engineering. This work builds upon these efforts by using computational ballistic impact simulations to predict the complex high strain-rate responses of various nickel-based HEAs fabricated by the DEVCOM ARL High-Throughput Materials Discovery for Extreme Conditions (HTMDEC) program. To capture the rate-dependent nature of the HEAs, the elasto-plastic Cowper-Symonds model was calibrated against experimental quasistatic uniaxial tension data and experimental Split-Hopkinson Pressure Bar (SHPB) data. Calibrating the rate-sensitivity parameters of the model allowed for direct implementation into a ballistic impact simulation in ABAQUS through a Vectorized User Material (VUMAT) subroutine. The ballistic impact simulation is used to predict the depth of penetration (DOP) of the projectile after impacting the HEA target. The DOP is directly used to evaluate each HEA’s performance, where a reduced DOP indicates a stronger, less penetrable material. To minimize the DOP and determine the presence of any relationships or correlations between the chosen performance metric (DOP) and the parameters of the simulation (projectile/target dimensions and material propertie
2025-04-09 09:00:00
