Phase engineering in nanocrystalline high-entropy alloy composites to achieve strength-plasticity synergy

In this work, the strength-plasticity synergy of Al/CoCrFeNi nanocrystalline high-entropy alloy composite (nc-HEAC) prepared by laser-inert gas condensation is achieved via nanoscale diffusion induced phase transition (DIPT) process. The yield strength and elongation of the 16%-Al/CoCrFeNi nc-HEAC annealed at 900 °C were 1338 MPa and 12.1%, showing the combination of outstanding strength and considerable ductility. The synergy of multiple strengthening mechanisms were revealed. Driving the phase transition of nanocrystalline dual-phase composites by thermal diffusion establishes a novel phase engineering design strategy for high-performance alloys.