%0 journal article
%@ 1359-6462
%A Silva, D.D.S.,Bertoli, G.,Neto, N.D.C.,Schell, N.,Clarke, K.D.,Kaufman, M.J.,Clarke, A.J.,Coury, F.G.,Bolfarini, C.

%D 2024
%J Scripta Materialia
%N 
%P 116264 
%R doi:10.1016/j.scriptamat.2024.116264
%T Computational thermodynamics-guided alloy design and phase stability in CoCrFeMnNi-based medium- and high-entropy alloys: An experimental-theoretical study
%U https://doi.org/10.1016/j.scriptamat.2024.116264
 
%X A computational thermodynamics approach has been employed to design CoCrFeMnNi-based medium- and high-entropy alloys (M/HEAs) with systematically varied compositions (Co((80-X)/2)Cr((80-X)/2)FeXMn10Ni10 with x = 30, 40, and 50 at.%) and phase stability. Since the formation of sigma phase, usually brittle and undesirable, is a common concern, when this class of alloys is subjected to elevated temperatures (600–1000 °C), predicting its formation becomes essential. Thus, its formation and the phase equilibria were studied using the CALPHAD method, and two empirical methods, namely, valence electron concentration (VEC) and paired sigma-forming element (PSFE). Isothermal aging treatments at 900–1100 °C for 20 h were performed, since CALPHAD and VEC/PSFE predictions diverged. Both prediction methods were compared with experimental characterization by a combination of scanning electron microscopy and high-energy synchrotron X-ray diffraction. The predictions from the VEC/PSFE and CALPHAD calculations (depending on the database used) were shown to be quite accurate.