New approach to model the yield strength of body-centered cubic solid solution refractory high-entropy alloys

A data fitting approach is used in the present work for modeling the yield strength of single-phase body-centered cubic (bcc) refractory high-entropy alloys (RHEAs) in the Al-Hf-Nb-Mo-Ta-Ti-V-Zr system. It is suggested that a polynomial equation could be used for modeling the strength of solid solution alloys where an experimental dataset containing more than 80 data is used for fitting and obtaining optimized polynomial coefficients. The comparison results show that the predictions are in good agreement with experimental data indicating that the proposed polynomial could be used for modeling the strength of RHEAs. To show how the developed polynomial can be applied in designing of RHEAs, the alloy system Hf-Mo-Nb-Ta-Ti-V-Zr is selected as an example and the strength of designed RHEAs within this system is investigated by the developed polynomial. The results show that the strength of alloys within this system increases by increasing the amount of Mo and Zr, while the strength of alloys decreases by increasing the amount of Ti. Moreover, the results indicate that the strength of alloys increases with increasing the values of parameters atomic size difference (ASD) and valence electron concentration (VEC). The developed polynomial can be considered as a straightforward method for assessing the strength of solid solution RHEAs, although it does not explain the mechanisms involved in the strengthening of alloys.