EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

High Entropy Alloys (HEAs) have attracted significant attention in the past decade due to the ability to form a single solid solution phase by breaking the conventional alloying strategy of having a single base metal. This has resulted in a variety of microstructures and properties that compete with conventional alloys. Recently, powder metallurgy has appeared to be a promising alternative to ingot casting to fabricate HEAs. However, currently these alloys are developed starting from raw elemental powders which are atomized before use which is expensive and takes up time and energy. In this work, we propose the formation of HEAs by using fully pre-alloyed powders from conventional available alloys (“commodity” powders) as raw materials that would act as source of the alloying components of the HEA (Ni, Co, Fe, Cr, Mo). Those commodity powders are available in the market in big quantities and proper cost. The selected available alloys, as gas atomised powders, are Inconel, Cobalt-Chrome, Invar and Stainless Steel. Different parameters based on the entropy and enthalpy of mixing and the atomic radii of the alloying elements were used to evaluate the suitability to develop a HEA after the powder route consolidation. Also, the valence electron concentration was used to predict the formation of a unique FCC or BCC phase. An attempt to produce a HEA by this innovative route based on these five elements was accomplished using the proper mix of the commodity powders and subsequent field assisted sintering and annealing. A fully FCC monophasic structure was obtained which demonstrates feasibility of the proposed methodology.