Atomistic mechanism of elastic softening in metallic glass under cyclic loading revealed by molecular dynamics simulations

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

18 Scopus Citations
View graph of relations

Detail(s)

Original languageEnglish
Pages (from-to)5-10
Journal / PublicationIntermetallics
Volume68
Publication statusPublished - 1 Jan 2016

Abstract

Metallic glasses (MGs) have a great potential for structural applications due to their high strength; however, they soften under cyclic loadings and exhibit low fatigue endurance limits. To understand the softening mechanism, molecular dynamics simulations were carried out to study the Cu50Zr50 MG within the nominal elastic regime, which clearly show that the quasi-static elastic modulus of the MG softens with either the decreasing cyclic frequency or increasing stress amplitude. Through the extensive analysis of the atomic trajectories, we found the complex elastic softening behavior is related to the activation of string-like liquid-like sites and atomic bond breaking in the cyclically deformed amorphous structure. Our current finding provides a quantitative insight into the atomistic mechanism of damage in MGs under cyclic loadings, also shedding light on the important mechanisms for fatigue damage initiation in amorphous solids.

Research Area(s)

  • Anelasticity, Fatigue resistance and crack growth, Metallic glasses, Molecular dynamics simulation, Plastic deformation mechanisms