Novel Alloy Design Concepts Enabling Enhanced Mechanical Properties of High Entropy Alloys

Abstract

The emergence of High Entropy Alloys (HEAs) in the world of materials has shifted the alloy design strategy based on a single principal element to the multi-principal elements where compositional space can cover almost the entire span of the higher dimensional phase diagrams. This approach can provide advanced materials with unique properties, including high strength with sufficient ductility and fracture toughness and excellent corrosion and wear resistance for a wide range of temperatures due to the concentrated alloying that cannot be obtained by traditional microalloying based on a single principal element. In addition, the alloy design approach provides new alloy systems in astronomical numbers with variety of microstructural attributes that can yield different properties, and hence conventional trial and error experimental methods for alloy development are redundant. With the help of high throughput experiments along with efficient computational tools, and artificial intelligence, mechanisms based mechanistic development of the multi-principal element alloys with tailored solid solution strengthening, stacking fault energy and microstructure is possible. The current review discusses the various design strategies based on multi-principal elements alloys in semblance with the desired mechanical properties dictated by the micro mechanisms associated with them to overcome the bottlenecks presented by the conventional approaches with possible breakthrough applications. The article will shed light on the current status as well as the future prospects of using these approaches to design novel HEAs.

A liquid metal-based process for tuning the thermoelectric properties of bismuth indium systems

“…30 Alloying metals can enable tuning of their micro/nanostructures and crystal orientations after solidification. [31][32][33] It is known that obtaining small grain sizes is necessary for intensification of phonon scattering. 34 Since the phenomenon of heat transport is dominated by phonons, the enhancement of phonon scattering reduces heat exchange.…”

Understanding the evolution of catalytically active multi-metal sites in a bifunctional high-entropy alloy electrocatalyst for zinc–air battery application

“…15,16 This class of alloys is termed multi-composition or multi-principal metal alloys 17 and is generally referred to as high-entropy alloys (HEAs) because entropy is the stabilization force. 18 These HEAs exhibit interesting hybrids of structural and mechanical 19 properties, such as better tensile strength, flexibility, ductility, corrosion resistance, etc. as well as electrical and electrochemical properties.…”

Diseño de aleación de alta entropía de alto desempeño mecánico en condiciones de bajas y altas temperaturas para aplicaciones energéticas y aeroespaciales.

“…El diseño de materiales metálicos avanzados conlleva una clara comprensión de los fenómenos metalúrgicos, físicos y mecánicos de las aleaciones para cumplir funcionalmente con los objetivos de aplicación propuestos en la etapa inicial del diseño [219][220][221][222]. Ejemplo de lo anterior es la reducción de peso en el área automotriz y la fabricación de materiales avanzados de bajo costo con altas prestaciones para altas y bajas temperaturas debido a las demandas de las industrias energéticas y aeroespaciales [15,[22][23][24][25][223][224][225].…”

“…El diseño de la aleación no se basa simplemente en la estabilidad de fases, también se debe considerar los mecanismos de refuerzo para aplicaciones funcionales del material específicas como lo es la respuesta mecánica a bajas temperaturas y altas temperaturas [33][34][35]98,220]. La respuesta mecánica a altas temperaturas principalmente se encuentra gobernada por el refuerzo mecánico de precipitación, permitiendo aumentar la respuesta a la fluencia [234][235][236][237][238].…”