Bulk ultrafine grained/nanocrystalline metals were fabricated via slow cooling for the first time.

Vanadium (V) alloys, such as V-Cr, V-Ti, and V-Cr-Ti alloys, are promising candidates for structural components in fusion energy systems because of their low activation, excellent radiation resistance, good compatibility with liquid lithium, and high ductility. Despite these advantages, the limited high-temperature strength and poor creep performances of V alloys have constrained their operating temperature range, challenging the application of these materials over the past few decades. The mechanical behavior is strongly dependent on microstructural features, including precipitates, intergranular and intragranular boundaries, dislocations, and point defects. At the same time, these features serve as preferable sites for solute or impurity atoms to segregate. The elemental segregation alters the local chemistry and stability of these defects, influencing microstructural evolutions and various materials properties that are essential for fusion energy applications. This review paper aims to provide a comprehensive overview of experimental and computational studies on elemental segregation and solute/impurity effects on the mechanical behaviors and microstructural evolution in V alloys. The conventional and advanced manufacturing processes of V alloys will be also discussed. Finally, this review will provide a concise perspective on the potential research directions of V alloys for future fusion reaction applications.