Scientific exploration in the field of high entropy alloys, known as HEAs, has recently exploded. First reported in about 2004, HEAs were defined originally as a blend of five or more elements with concentrations between 5 to 35 atom percent, and with a strong preference towards single-phase, solid solution metallic alloys. Later, the field branched to include intermetallic and ceramic compounds, alloys with as few as three principle elements, and microstructures with any number and type of phases. Today, researchers face vast combinations of elements with which to work, and they eagerly seek to learn more about HEA compositions, microstructures, promising property combinations, and opportunities for a wide variety of applications in both structural and functional materials. HEA development offers tremendous potential not only for expanding scientific knowledge, but also for creating a broad range of revolutionary products for strategic, economic, and national security benefits.
“Defining Pathways for Realizing the Revolutionary Potential of High Entropy Alloys” is organized by TMS on behalf of the Defense Advanced Research Projects Agency (DARPA) via the Air Force Research Laboratory (AFRL). The study examines the extensive work being performed in this emerging field with the goal of providing science and technology pathways to accelerate realization of the wide-reaching potential of HEAs in some key application areas and alloy categories.
- Describes the current state of HEA technologies.
- Provides a prioritized list of applications and alloy domains of most promise, particularly for defense-related applications.
- Identifies the key technology gaps, barriers, and enablers of the next stage of research in areas with the greatest potential for impact.
- Proposes recommendations and action plans toward significant progress within the next three to five years in the scientific exploration, engineering development, and industrial implementation of HEAs.
Resources for Sharing Study Content
- Suggested Citation: The Minerals, Metals & Materials Society (TMS), Defining Pathways for Realizing the Revolutionary Potential of High Entropy Alloys (Pittsburgh, PA: TMS 2021). Electronic copies available at www.tms.org/HEApathways.