Impact of Fabrication Processes on the Mechanical Performance of AlCoCrFeNi-Based High-Entropy Alloys: A Review

AlCoCrFeNi-based high-entropy alloys have garnered significant attention for high-end applications in aerospace, marine engineering, and the nuclear industry due to their exceptional comprehensive properties, including high strength and good corrosion resistance. However, their widespread application is critically hindered by a fatal disadvantage: poor ductility. Optimizing the ductility of this alloy system has therefore become a key research priority. Optimizing their ductility has emerged as a key research priority in recent literature. This review systematically examined the influences of diverse fabrication techniques on the mechanical properties, particularly ductility, of these alloys. Melting routes (vacuum arc melting and vacuum induction melting), powder consolidation (spark plasma sintering and hot pressing), and additive manufacturing (selective laser melting, laser melting deposition, electron beam melting, and wire arc additive manufacturing) were covered in this review. This review underscores that while each fabrication route offers distinct advantages, future breakthroughs require multi-process hybridization, data-driven optimization, and precise control of precipitation kinetics to overcome the strength–ductility trade-off and enable large-scale applications of AlCoCrFeNi-based HEAs.