Correlation between mechanical properties and thermodynamic parameters of dual-fcc-phase CoCrFeCuxNi (x=1, 1.71) and CoCu1.71FeMnNi

In this study, the correlations between the total enthalpies and microstructural/mechanical properties of dual-fcc-phase CoCrFeMnNi, CoCrFeCu1.71Ni and CoCu1.71FeMnNi were studied. The reduction of mixing enthalpy (Delta H-mix) and lattice strain energy (Delta H-el) act as the driving force for phase-separation and induces the dual-fcc-phase structure The reduction of chemical enthalpy/lattice strain energy (Delta H-tot = Delta H-mix + Delta H-el) upon phase separation was calculated to be 5.44 KJ/mol, 2.89 KJ/mol and 0.72 KJ/mol for CoCrFeCu1.71Ni, CoCrFeMnNi and CoCu1.71FeMnNi, respectively. The phase separation distance is dependent on reduction of Delta H-tot and the average distance increased with increase of Delta H-tot. The correlation between the mechanical properties and thermodynamic parameters was demonstrated through the interrelationship between strength, spacing of dendritic and/or lamella structure and thermodynamic parameters. (C) 2020 Elsevier B.V. All rights reserved.