Coupling effect of penetration and explosion in a novel high-entropy alloy energetic structural material under ballistic impact

A novel dual-phase body-centered cubic TiZrHfTa_0.5W_0.5 high-entropy alloy energetic structural material has been developed that exhibits a pronounced coupling of penetration and explosion under ballistic impact. This is attributed to the alloy mechanical properties, high density and superior energetic characteristics. Extensive strain hardening and appreciable plasticity are features of the phase transformation from a body-centered cubic matrix to a hexagonal cubic phase structure at high strain rates. Equiaxed sub-grains are formed via dislocation slip and grain subdivision under quasi-static loadings, while a martensitic transformation is mediated by the significant increase in martensite nucleation sites under dynamic loadings. The observed enhanced terminal effects originate from the kinetic and chemical energy of the residual energetic projectile, resulting in a rear target plate petaling tearing failure. The penetration and explosion behavior associated with the energetic projectile when impacting double-spaced plates is quantitatively evaluated using the relationship between the perforation and damaged region diameters and impact velocity.