Electrometallurgy Today, 2026, №02

2026 №02 (04)

DOI of Article
10.37434/sem2026.02.05

2026 №02 (06)

"Suchasna Elektrometallurgiya" (Electrometallurgy Today), 2026, 2, 39-51 pages

Intermetallics of the Fe–Al system: current understanding of structure, properties and applications

Yu.V. Kostetskyi^1,3, M.P. Naumenko¹, O.A. Rokytska^2,3

¹E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: y.kostetsky@paton.kiev.ua
²2Frantsevich Institute for Problems of Materials Science of NASU. 3 Omeliana Pritsaka Str., 03142, Kyiv, Ukraine
³National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Ukraine. 37 Prospect Beresteiskyi, 03056, Ukraine

Abstract
This paper summarizes the current state of knowledge on phase equilibria, microstructure, and mechanical and functional properties of Fe–Al alloys. Particular attention is given to the features of formation and thermal stability of the A2, Fe3Al (D03), and FeAl (B2) phases, as well as to the influence of ordering and defect structure on strength and ductility. The roles of vacancies, grain boundaries, and dislocations in the temperature dependence of yield strength, including anomalous strengthening effect, are analyzed. It is shown that alloying with Cr, Mo, W, V, Ni, B, Ti, Nb, and Si significantly affects high-temperature strength, corrosion resistance, grain-boundary cohesion, and increase in the ductility of Fe–Al intermetallics. The main application areas of Fe–Al alloys in high-temperature structural components, wear-resistant parts, coatings, and composite materials are outlined. A review of the literature indicates that the rational combination of alloying and modern processing technologies broadens the prospects for the practical use of Fe–Al intermetallics as a cost-effective alternative to conventional high-temperature alloys. 63 Ref., 1 Tabl., 7 Fig.
Keywords: iron-aluminides, phase equilibrium, ordered D03 and B2 phases, defect structure, anomalous strengthening, alloying, high-temperature strength, corrosion resistance

Received: 17.03.2026
Received in revised form: 04.05.2026
Accepted: 20.05.2026
Posted online: 27.05.2026

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Suggested Citation

Yu.V. Kostetskyi, M.P. Naumenko, O.A. Rokytska (2026) Intermetallics of the Fe–Al system: current understanding of structure, properties and applications. Electrometallurgy Today, 02, 39-51. https://doi.org/10.37434/sem2026.02.05