Design and optimization of quinary high entropy alloy systems with single-phase microstructures from conventional alloy systems

• Developed a constraint-driven framework for High Entropy Alloy (HEA) design by leveraging the compositional logic of conventional engineering alloys. • Integrated thermodynamic stability criteria with manufacturability filters including melting point compatibility, atomic solubility index, and vapor pressure compatibility to refine alloy selection. • Generated over 60 equiatomic quinary alloy systems from 15 industrial prototype alloys, with a significant portion representing novel, literature-unreported compositions. • Successfully fabricated a CuFeNiMnAl alloy via Directed Energy Deposition (DED), exhibiting a dominant FCC structure, high hardness (∼560 HV), lattice contraction, and a measured density of 7 g/cm 3 . High-entropy alloy (HEA) discovery has traditionally relied on theoretical stability criteria and random compositional permutations, often overlooking practical manufacturability and experimental viability. In this study, we present a constraint-driven alloy design framework that enables early-stage development of manufacturable quinary equiatomic HEAs derived directly from conventional engineering alloys. Beyond the classical thermodynamic screening parameters, our framework incorporates manufacturability filters: melting point compatibility (ΔT mc ), atomic solubility index, ( S ¯ ) and vapor pressure parameter (P v ), targeting additive manufacturing (AM) processability. A flexible web-based platform was developed, allowing users to input any conventional alloy and generate new HEA systems according to the described criteria. We applied this framework to 15 industrial prototype alloys, generating over 60 quinary HEA candidates, many of which are previously unreported. One predicted composition, CuFeNiMnAl, was successfully fabricated using Directed Energy Deposition (DED), exhibiting a fine-grained FCC structure, high hardness (∼560 HV), and high densification (∼7.1 g/cm 3 ) relative to its parent alloy, nickel aluminum bronze. This experimental validation confirms the framework’s ability to deliver novel, manufacturable HEAs derived from real alloy systems. By integrating manufacturability constraints into early-stage design, this work provides a scalable, data-efficient pathway to application-ready HEAs, bridging computational discovery with industrial implementation.