The preparation of high-entropy refractory alloys by aluminothermic reduction process.

High-entropy refractory alloys (HERA) were synthesized by self-propagating high-temperature synthesis (SHS) using aluminothermic reduction. The amount of reducer was selected according to the reaction stoichiometry in such a way as to provide the necessary combustion temperature to ensure a complete phase separation and obtain the target alloys without the presence of extraneous impurities. The combustion product was formed in the form of a high-temperature multi-component melt and phase separation took place under the influence of gravitational force. In this case, the aluminum oxide remains at the top of the melt, while the denser alloy sinks to the bottom. Combustion products after phase separation represent solid, compact samples with magnetic properties, as well as self-heating behavior when subjected to mechanical impact. Single-phase high entropy alloys of MnFeCoNiCu, MnFeCoNiCr, Al2FeCoNiCr, AlFe7Co3Ni2Cu0.4 composition were produced and characterized. [ABSTRACT FROM AUTHOR]