A robust modeling framework for predicting nanovoid structures and energetics in FCC metals

Abstract

Understanding the structures and energetics of vacancy-type defects is crucial for comprehending defect evolution in metals, yet current methods face significant challenges, particularly regarding nanovoids in FCC metals. Here, we developed a robust modeling framework to accurately predict the structure and energetics of nanovoids in FCC metals. We demonstrated that stable nanovoid structures can be efficiently determined by maximizing the coordination number among vacancies and identified a linear relationship between nanovoid formation energies and their compactness factors. Notably, we revealed six discrete binding energy levels in nanovoid–vacancy interactions, each correlated solely with changes in compactness factors. Our new model has been validated through first-principles calculations and experiments, demonstrating clear advantages over conventional methods. This model effectively handles arbitrarily sized nanovoids in FCC metals, capturing atomic-scale variations, and providing key insights into vacancy-related damage, along with essential tools for multiscale modeling and the development of new metal interatomic potentials.