Cost-aware design advances structural high-entropy alloys

A review of high- and medium-entropy alloys identifies iron-rich, cobalt-free compositions as a promising route toward structural materials that combine competitive strength and ductility with lower material costs. The review focuses on the cost of constituent elements, particularly cobalt, as a major obstacle to broad industrial adoption, and examines how composition, processing and computational design can be combined to develop more economically viable alloys. Because this is a review, its conclusions synthesize and assess earlier research rather than report a new material test or industrial deployment.

The review analyzes four thermodynamic and structural parameters: valence electron concentration, atomic size mismatch, mixing enthalpy and stacking fault energy. These variables are considered in relation to phase stability and deformation mechanisms. It also examines strengthening strategies for lower-cost systems, including precipitation hardening, grain refinement, heterogeneous microstructures and solidification-induced structural architecture.

The central approach is cost-aware alloy design, in which composition, processing and performance are evaluated together rather than treating mechanical properties in isolation. Alloys with low stacking-fault energy receive particular attention because they can exploit twinning-induced plasticity and transformation-induced plasticity during deformation. Eutectic high-entropy alloys are also presented as an industrially scalable dual-phase design strategy, combining complementary phase contributions with the goal of strengthening and economic viability.

CALPHAD calculations and machine-learning-assisted screening are discussed as tools for accelerating the identification of candidate compositions. The review places these computational approaches within a broader framework that includes simplified chemical formulations, explicit cost-performance metrics and scalable processing routes. Future priorities include high-throughput alloy design organized around cost constraints, multifunctional evaluations that include corrosion and wear resistance, and studies of long-term fatigue reliability.

The review’s overall conclusion is that compositional simplification, cost-performance assessment, computational screening and scalable processing provide a combined route for developing robust structural high- and medium-entropy alloys. Its scope is a review of promising design and processing directions, not a demonstration that every iron-rich or cobalt-free composition will provide equivalent mechanical performance or commercial readiness.

Subject of Research: Cost-aware design of structural high- and medium-entropy alloys

Article Title: High performance yet cost effective structural high-entropy alloys: a review

Article References: Mehranpour, M. S., Sohrabi, M. J., Mirzadeh, H., Khorrami, M. S., & Kim, H. S. (2026). High performance yet cost effective structural high-entropy alloys: a review. Journal of Materials Science. https://doi.org/10.1007/s10853-026-13651-6

Image Credits: AI Generated

DOI: 10.1007/s10853-026-13651-6

Keywords: high-entropy alloys, medium-entropy alloys, cobalt-free alloys, iron-rich alloys, strength and ductility, CALPHAD, machine learning, eutectic alloys, materials processing, High, performance, cost