Universal correlation between electronic factors and solute-defect interactions in bcc refractory metals

TL;DR

This study uncovers a universal linear correlation between electronic factors and solute-defect interaction energies in bcc refractory metal alloys, offering a new way to engineer alloy properties.

Contribution

It introduces a universal correlation linking electronic structure features to solute-defect interactions in bcc refractory metals, independent of defect type or site.

Findings

Correlation is linear for specific solute-matrix pairs.

The relation holds across various defect types and sites.

Provides a quantitative electronic-structure-based design guideline.

Abstract

The interactions between solute atoms and crystalline defects such as vacancies, dislocations, and grain boundaries play an essential role in determining physical, chemical and mechanical properties of solid-solution alloys. Here we present a universal correlation between two electronic factors and the solute-defect interaction energies in binary alloys of body-centered-cubic (bcc) refractory metals (such as W and Ta) with transition-metal substitutional solutes. One electronic factor is the bimodality of the d-orbital local density of states for a matrix atom at the substitutional site, and the other is related to the hybridization strength between the valance sp- and d-bands for the same matrix atom. Remarkably, the correlation is independent of the types of defects and the locations of substitutional sites, following a linear relation for a particular pair of solute-matrix elements. Our findings provide a novel and quantitative guidance to engineer the solute-defect interactions in alloys based on electronic structures.