Structural rearrangements governing Johari-Goldstein relaxations in metallic glasses

Hai Bin Yu, Ranko Richert, Konrad Samwer

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

The Johari-Goldstein secondary (b) relaxations are an intrinsic feature of supercooled liquids and glasses. They are crucial to many properties of glassy materials, but the underlying mechanisms are still not established. In a model metallic glass, we study the atomic rearrangements by molecular dynamics simulations at time scales of up to microseconds. We find that the distributions of single-particle displacements exhibit multiple peaks, whose positions quantitatively match the pair distribution function. These are identified as the structural signature of cooperative string-like excitations. Furthermore, the most probable time of the string-like motions coincides with the b-relaxation time as probed by dynamical mechanical simulations over a wide temperature range and is consistent with a theoretical model. Our results provide insights into the long-standing puzzle regarding the structural origin of b relaxations in glassy metallic materials.

Original languageEnglish (US)
Article numbere1701577
JournalScience advances
Volume3
Issue number11
DOIs
StatePublished - Jan 1 2017

Fingerprint

Glass
Molecular Dynamics Simulation
Theoretical Models
Temperature

ASJC Scopus subject areas

  • Medicine(all)

Cite this

Structural rearrangements governing Johari-Goldstein relaxations in metallic glasses. / Yu, Hai Bin; Richert, Ranko; Samwer, Konrad.

In: Science advances, Vol. 3, No. 11, e1701577, 01.01.2017.

Research output: Contribution to journalArticle

@article{bbfb8a86b605470590ab557198ed675b,
title = "Structural rearrangements governing Johari-Goldstein relaxations in metallic glasses",
abstract = "The Johari-Goldstein secondary (b) relaxations are an intrinsic feature of supercooled liquids and glasses. They are crucial to many properties of glassy materials, but the underlying mechanisms are still not established. In a model metallic glass, we study the atomic rearrangements by molecular dynamics simulations at time scales of up to microseconds. We find that the distributions of single-particle displacements exhibit multiple peaks, whose positions quantitatively match the pair distribution function. These are identified as the structural signature of cooperative string-like excitations. Furthermore, the most probable time of the string-like motions coincides with the b-relaxation time as probed by dynamical mechanical simulations over a wide temperature range and is consistent with a theoretical model. Our results provide insights into the long-standing puzzle regarding the structural origin of b relaxations in glassy metallic materials.",
author = "Yu, {Hai Bin} and Ranko Richert and Konrad Samwer",
year = "2017",
month = "1",
day = "1",
doi = "10.1126/sciadv.1701577",
language = "English (US)",
volume = "3",
journal = "Science advances",
issn = "2375-2548",
publisher = "American Association for the Advancement of Science",
number = "11",

}

TY - JOUR

T1 - Structural rearrangements governing Johari-Goldstein relaxations in metallic glasses

AU - Yu, Hai Bin

AU - Richert, Ranko

AU - Samwer, Konrad

PY - 2017/1/1

Y1 - 2017/1/1

N2 - The Johari-Goldstein secondary (b) relaxations are an intrinsic feature of supercooled liquids and glasses. They are crucial to many properties of glassy materials, but the underlying mechanisms are still not established. In a model metallic glass, we study the atomic rearrangements by molecular dynamics simulations at time scales of up to microseconds. We find that the distributions of single-particle displacements exhibit multiple peaks, whose positions quantitatively match the pair distribution function. These are identified as the structural signature of cooperative string-like excitations. Furthermore, the most probable time of the string-like motions coincides with the b-relaxation time as probed by dynamical mechanical simulations over a wide temperature range and is consistent with a theoretical model. Our results provide insights into the long-standing puzzle regarding the structural origin of b relaxations in glassy metallic materials.

AB - The Johari-Goldstein secondary (b) relaxations are an intrinsic feature of supercooled liquids and glasses. They are crucial to many properties of glassy materials, but the underlying mechanisms are still not established. In a model metallic glass, we study the atomic rearrangements by molecular dynamics simulations at time scales of up to microseconds. We find that the distributions of single-particle displacements exhibit multiple peaks, whose positions quantitatively match the pair distribution function. These are identified as the structural signature of cooperative string-like excitations. Furthermore, the most probable time of the string-like motions coincides with the b-relaxation time as probed by dynamical mechanical simulations over a wide temperature range and is consistent with a theoretical model. Our results provide insights into the long-standing puzzle regarding the structural origin of b relaxations in glassy metallic materials.

UR - http://www.scopus.com/inward/record.url?scp=85041930781&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85041930781&partnerID=8YFLogxK

U2 - 10.1126/sciadv.1701577

DO - 10.1126/sciadv.1701577

M3 - Article

C2 - 29159283

AN - SCOPUS:85041930781

VL - 3

JO - Science advances

JF - Science advances

SN - 2375-2548

IS - 11

M1 - e1701577

ER -