Novel Materials for Kinetic Energy Penetrators

MATSYS proposes to develop and demonstrate novel tungsten-based alloys with nanocrystalline microstructure and a scalable manufacturing process for cost-effective fabrication of kinetic energy (KE) penetrators. Depleted Uranium (DU) alloys demonstrate superior ballistic performance over conventional tungsten heavy alloys (WHA). However, residue from DU munitions presents issues, such as the cleanup of a persistent health and environmental hazard. The increased performance of DU is attributed to a localized flow-softening behavior, more commonly referred to as adiabatic shear. WHA alloys are a natural candidate for KE penetrator applications because of their high density. However, they do not generally show any strain localization desires for self-sharpening behavior. Recent work has shown that tungsten-based alloys with nanocrystalline microstructure exhibit strain localization and extraordinary promise as a penetrator material. Our approach is to use thermodynamic modeling to design new stable nanocrystalline tungsten-based alloys, and then use high energy milling to refine the microstructure of the powder for the selected compositions and consolidate these powders into bulk, fully dense, nanostructured material. This effort will use thermodynamic modeling to identify potential alloy compositions, and combine our unique expertise in high energy milling and instrumented-Hot Isostatic Pressing to develop bulk nanostructured tungsten-based alloys for next generation KE munitions.