A structural modeling approach to solid solutions based on the similar atomic environment

TL;DR

This paper introduces a novel structural modeling approach for solid solutions based on atomic environment similarity, enabling better prediction of material structures with short-range order and disordered configurations.

Contribution

The paper presents a new similarity-based modeling method for solid solutions, validated against existing techniques and applied to various high-entropy and medium-entropy alloys.

Findings

The SAE method accurately describes configurational deviations.

Validation shows consistency with the SQS method.

Application to alloys reveals insights into structural properties.

Abstract

Solid solution is an important way to enhance the structural and functional performances of materials. In this work, we develop a structural modeling approach to solid solutions based on the similar atomic environment (SAE). We propose the similarity function associated with any type of atom cluster to describe quantitatively the configurational deviation from the desired solid solution structure that is fully disordered or contains short-range order (SRO). In this manner, the structural modeling for solid solution is transferred to a minimization problem in the configuration space. Moreover, we pay efforts to enhance the practicality and functionality of this approach. The approach and implementation are demonstrated by the cross-validations with the special quasi-random structure (SQS) method. We apply the SAE method to the typical quinary CoCrFeMnNi high-entropy alloy, continuous binary Ta-W alloy and ternary CoCrNi medium-entropy alloy with SRO as prototypes. In combination with ab initio calculations, we investigate the structural properties and compare the calculation results with experiments.