Linking Thermal History to Shear Band Interaction and Macroscopic Ductility in Metallic Glasses

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Sun, Lechuan, Zhang, Shan, Xu, Bin, Su, Rui, Wang, Yunjiang, Guan, Pengfei
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915692430753792
author Sun, Lechuan
Zhang, Shan
Xu, Bin
Su, Rui
Wang, Yunjiang
Guan, Pengfei
author_facet Sun, Lechuan
Zhang, Shan
Xu, Bin
Su, Rui
Wang, Yunjiang
Guan, Pengfei
contents Shear band propagation and interaction are critical to the mechanical performance of metallic glasses and are strongly governed by thermal history, yet their microscopic mechanisms remain unclear. Here, using molecular dynamics simulations combined with a state-of-the-art annealing protocol, we systematically investigate these behaviors in a model metallic glass across effective quenching rates spanning six orders of magnitude. Through a double-notch model, we show that the normalized interaction distance relative to the single shear band width is significantly larger in slowly quenched samples than in rapidly quenched ones. Atomic-scale analysis reveals that rapidly quenched samples exhibit a high density of pre-existing soft regions, which trigger correlated shear transformation zones through local vortex fields, resulting in propagation path locking and weak inter-band coupling. In contrast, slowly quenched samples exhibit enhanced structural heterogeneity and a right-shifted activation energy spectrum, promoting a single large-scale vortex field ahead of the shear band front. This field facilitates long-range stress transmission and induces shear band deflection, convergence, and coalescence, a transition resembling a "shielding effect" in fracture mechanics, where vortex-mediated disturbances destabilize the advancing shear band front. Our findings establish a direct microscopic connection between glass stability and shear-band-mediated plasticity and suggest that regulating shear band interactions offers a promising route to enhance the room-temperature ductility of metallic glasses.
format Preprint
id arxiv_https___arxiv_org_abs_2512_20121
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Linking Thermal History to Shear Band Interaction and Macroscopic Ductility in Metallic Glasses
Sun, Lechuan
Zhang, Shan
Xu, Bin
Su, Rui
Wang, Yunjiang
Guan, Pengfei
Materials Science
Shear band propagation and interaction are critical to the mechanical performance of metallic glasses and are strongly governed by thermal history, yet their microscopic mechanisms remain unclear. Here, using molecular dynamics simulations combined with a state-of-the-art annealing protocol, we systematically investigate these behaviors in a model metallic glass across effective quenching rates spanning six orders of magnitude. Through a double-notch model, we show that the normalized interaction distance relative to the single shear band width is significantly larger in slowly quenched samples than in rapidly quenched ones. Atomic-scale analysis reveals that rapidly quenched samples exhibit a high density of pre-existing soft regions, which trigger correlated shear transformation zones through local vortex fields, resulting in propagation path locking and weak inter-band coupling. In contrast, slowly quenched samples exhibit enhanced structural heterogeneity and a right-shifted activation energy spectrum, promoting a single large-scale vortex field ahead of the shear band front. This field facilitates long-range stress transmission and induces shear band deflection, convergence, and coalescence, a transition resembling a "shielding effect" in fracture mechanics, where vortex-mediated disturbances destabilize the advancing shear band front. Our findings establish a direct microscopic connection between glass stability and shear-band-mediated plasticity and suggest that regulating shear band interactions offers a promising route to enhance the room-temperature ductility of metallic glasses.
title Linking Thermal History to Shear Band Interaction and Macroscopic Ductility in Metallic Glasses
topic Materials Science
url https://arxiv.org/abs/2512.20121