2026 Ishtiaq FCC Alloy Short Range Order

Multi-principal element alloys have emerged as an important class of structural materials owing to their exceptional combinations of strength, ductility, and microstructural stability. Increasing evidence suggests that chemical short-range ordering plays a critical role in governing these properties by modifying local bonding, defect energetics, and deformation pathways. Yet, a coherent understanding of short-range order in face-centered cubic multi-principal element alloys remains elusive, not only because its formation and manifestation are highly sensitive to alloy chemistry and thermal history, but also because fundamental questions remain unresolved regarding how short-range order should be defined, measured, and interpreted in chemically complex solid solutions. In this review, we critically examine the current understanding of short-range order in face-centered cubic multi-principal element alloys, with emphasis on its thermodynamic origin, thermal evolution, quantitative descriptors, and multiscale characterization. A distinctive contribution of this review is the proposal of a practical correlative protocol for identifying 'true short-range order', with emphasis on the minimum evidence required to distinguish genuine short-range order from clustering, long-range ordered precipitates, and measurement-related artifacts.