Predicting the solid solution structure preference of multi-component alloys

Abstract

High-entropy alloys (HEAs) provide limitless opportunities to enhance material performance while predicting the thermodynamic properties and the structures rapidly within HEAs remain challenging. Herein, a new method (M2FEn) for rapidly predicting the formation enthalpies is provided. In contrast to Miedema's semi-empirical methodology, which solely calculates the mixing enthalpy, the M2FEn is capable of calculating the formation enthalpies of various solid solution structures, and by ordering these enthalpies, one can determine the preferred solid-solution structure for the single-phase alloy. The predicted structures using M2FEn are in line with first-principles calculations. The effectiveness of different extrapolation models for formation enthalpy has been assessed. The M2FEn with the Ouyang extrapolation model and the regular solution model have achieved a prediction accuracy of 95.8% and 95.4%, respectively for single-phase HEAs that were experimentally prepared. 28 common HEA elements were selected as the chemical space, and the formation enthalpies of all binary, ternary, quaternary, quinary and senary alloys, a total of 499149 various alloys were calculated by M2FEn. It is found that the BCC structure ratio increases with the increase of the principal element of the alloy. The M2FEn should potentially accelerate the development of novel, high-performance HEAs, enabling more efficient and cost-effective materials design processes.

Keywords

• High-entropy alloys
• Alloy design
• Structure prediction
• Formation enthalpies