Medium/high entropy alloys with heterogeneous structures for superior properties: A review

Heterogeneous structures, such as gradient, lamellar, and dual-phase configurations, have been prevalent in nature for ages and have been harnessed in diverse applications to achieve exceptional properties in man-made engineering materials. These heterogeneous structures not only enhance the mechanical properties of the structured material but also exhibit immense potential in functional materials, enabling unprecedented functionalities. High entropy alloys (HEAs), a cutting-edge alloy design concept centered on multi-principal elements, offer a vast compositional landscape. The integration of HEA with heterogeneous structures further broadens the prospects for discovering new materials with remarkable attributes. This review delves into several types of heterogeneous structures within HEAs, highlighting their superior mechanical and functional properties, including strength, ductility, dynamic shear toughness, fracture toughness, fatigue properties, and magnetic capabilities. Additionally, it explores their deformation mechanisms and strain-hardening capabilities. This article provides a comprehensive overview of heterogeneous structured HEA for achieving enhanced mechanical and functional performance. © 2024 The Author(s).