A novel computational model for isotropic interfacial energies in multicomponent alloys and its coupling with phase-field model with finite interface dissipation

In this work, a novel computational model for the description of the temperature- and compositiondependent isotropic interfacial energy in multicomponent alloys was first developed in the framework of the CALculation of PHAse Diagram (CALPHAD) approach and implemented in a home-made code. By linking to the open-source code for interfacial energy calculation in alloys, OpenIEC, the databases for isotropic gamma /liquid and gamma / gamma ' interfacial energies in Ni-Al, Ni-Cr, Al-Cr, and Ni-Al-Cr systems were then efficiently established. After that, a direct coupling strategy between the current CALPHAD interfacial energy database and the phase-field model with finite interface dissipation was proposed and applied to three-dimensional (3-D) phase-field simulations of the primary gamma dendritic growth in both Ni-Al and Ni-Al-Cr alloys during isothermal solidification. The effect of the interfacial energy on the morphology, tip growth rate, and partitioning coefficients in primary gamma dendrites of binary Ni-Al and ternary Ni-Al- Cr alloys was investigated by comprehensively comparing the phase-filed simulation results using the composition-/temperature-dependent interfacial energies with those using the constant value. It is anticipated that the presently developed CALPHAD model for interfacial energy is of general validity for different multicom ponent alloys and should be integrated with the phase-field model for quantitative simulation of their microstructure evolution. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

A novel computational model was developed to describe the temperature- and composition-dependent isotropic interfacial energy in multicomponent alloys using the CALculation of PHAse Diagram (CALPHAD) approach and implemented in a home-made code. By linking to the open-source code for interfacial energy calculation, databases for isotropic gamma/liquid and gamma/gamma' interfacial energies in different alloy systems were efficiently established. A direct coupling strategy between the CALPHAD interfacial energy database and the phase-field model was proposed and applied to three-dimensional phase-field simulations of dendritic growth in Ni-Al and Ni-Al-Cr alloys. The effect of interfacial energy on the morphology, growth rate, and partitioning coefficients of dendrites was investigated by comparing simulation results with composition/temperature-dependent interfacial energies and constant values. The developed CALPHAD model for interfacial energy is expected to be applicable to various multicomponent alloys and can be integrated with the phase-field model for quantitative simulation of microstructure evolution.