Zr-Ni-Ti energetic structural materials with superior strength-ductility synergy and energy release via eutectic design

Metallic energetic structural materials (ESMs) have long suffered from a fundamental trade-off between mechanical properties, processability and energy release characteristics that hinders large-scale ESM components fabrication. To overcome these limitations, this study exploits the eutectic characteristics of the Zr-Ni-Ti ternary system to engineer alloys with synergistic benefits of low liquidus temperature, superior mechanical properties, and high energy release potential. Hypo-eutectic and near-eutectic as-cast alloys in the Zr-rich region (Zr ≥ 60 at%) were systematically designed using CALPHAD (Calculation of Phase Diagrams) methodology, with Ni content as the primary compositional variable. Microstructural evolution during rapid solidification was systematically investigated to elucidate the non-equilibrium phase formation mechanisms. The simultaneous enhancement of strength and plasticity originates from a dual-phase architecture comprising α/β solid-solution matrix and NiZr 2 intermetallic phase, where heterophase interfaces induce strain accommodation through interfacial strain gradients. Thermal analysis confirmed excellent castability with low liquidus temperatures. The optimized Zr 72 Ni 15 Ti 13 alloy achieves compressive strength of (1408 ± 44) MPa with (9.94 ± 1.19)% fracture strain, outperforming most reported counterpart ESMs, such as Zr-based amorphous alloys, Zr-Ni-Ti alloys. Ballistic impact tests at 1397 m/s demonstrate high energy release of 3.216 kJ/g with quasi-static overpressure of 0.238 MPa. These results establish as-cast Zr-Ni-Ti alloys as promising candidates for next-generation reactive structural applications requiring integrated load-bearing and damage enhancement capabilities.