Ab initio simulations on the pure Cr lattice stability at 0K: Verification with the Fe-Cr and Ni-Cr binary systems

Abstract

Significant discrepancies have been observed and discussed on the lattice stability of Cr between the predictions from the ab initio calculations and the CALPHAD approach. In the current work, we carefully examined the possible structures for pure Cr and reviewed the history back from how Kaufman originally determined the Gibbs energy of FCC-Cr in the 1970s. The reliability of Cr lattice stability derived by the CALPHAD and ab initio approaches was systematically discussed. It is concluded that the Cr lattice stability based on the CALPHAD approach has large uncertainty. Meanwhile, we cannot claim that the ab initio HFCC-Cr is error-free as FCC-Cr is an unstable phase under ambient conditions. The present work shows that the ab initio HFCC-Cr can be a viable scientific approach. As both approaches have their limitations, the present work propose to integrate the ab initio results into the CALPHAD platform for the development of the next generation CALPHAD database. The Fe-Cr and Ni-Cr binary systems were chosen as two case studies demonstrating the capability to adopt the ab initio Cr lattice stability directly into the current CALPHAD database framework.

References in corpus (6)

• The Alloy Theoretic Automated Toolkit: A User Guide
• Phase stability of ternary fcc and bcc Fe-Cr-Ni alloys
• Thermodynamic properties of binary HCP solution phases from special quasirandom structures
• Extensible Structure-Informed Prediction of Formation Energy with Improved Accuracy and Usability employing Neural Networks
• DFTTK: Density Functional Theory ToolKit for High-throughput Lattice Dynamics Calculations
• Sensitivity estimation for calculated phase equilibria

Cited by in corpus (4)

• Thermodynamics and its Prediction and CALPHAD Modeling: Review, State of the Art, and Perspectives
• Genomic Materials Design: CALculation of PHAse Dynamics
• DFTTK: Density Functional Theory ToolKit for High-throughput Lattice Dynamics Calculations
• Investigation of ideal shear strength of dilute binary and ternary Ni-based alloys using first-principles calculations, CALPHAD modeling and correlation analysis