Cascade at local yield strain for silica and metallic glass

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Pingua, Nandlal, Rautela, Himani, Chatterjee, Roni, Karmakar, Smarajit, Chaudhuri, Pinaki, Sengupta, Shiladitya
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911015760822272
author Pingua, Nandlal
Rautela, Himani
Chatterjee, Roni
Karmakar, Smarajit
Chaudhuri, Pinaki
Sengupta, Shiladitya
author_facet Pingua, Nandlal
Rautela, Himani
Chatterjee, Roni
Karmakar, Smarajit
Chaudhuri, Pinaki
Sengupta, Shiladitya
contents We report observations of unusal \emph{first} plastic events in silica and metallic glasses in the shear startup regime at applied strain two orders of magnitude smaller than yield strain. The (non-Affine) particle displacement field during these events have complex real space structure with multiple disconnected cores of high displacement appearing at the \emph{same} applied strain under athermal quasistatic simple shear deformation, and identified by a ``cell based cluster analysis'' method. By monitoring the stress relaxation during the first plastic event by Langevin dynamics simulation, we directly show the cascade nature of these events. Thus these first plastic events are reminiscent of avalanches in the post-yielding steady state, but unlike the steady state avalanches, we show that these events are not system spanning. To understand the nature of these events, we tune three factors that are known to affect brittleness of a glass. These are (i) sample preparation history, (ii) inter-particle interactions and (iii) rigidity of the background matrix applying a ``soft matrix'' probe recently developed by some of us. In each case we show that such first plastic events are more probable in more ductile glasses. Our observations are consistent with the picture that more ductile materials are softer, implying that understanding the role of softness may be a promising route to develop microscopic quantifiers of brittleness and thus clarifying the physical origin of brittle-to-ductile transition.
format Preprint
id arxiv_https___arxiv_org_abs_2506_17129
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Cascade at local yield strain for silica and metallic glass
Pingua, Nandlal
Rautela, Himani
Chatterjee, Roni
Karmakar, Smarajit
Chaudhuri, Pinaki
Sengupta, Shiladitya
Soft Condensed Matter
Disordered Systems and Neural Networks
Statistical Mechanics
We report observations of unusal \emph{first} plastic events in silica and metallic glasses in the shear startup regime at applied strain two orders of magnitude smaller than yield strain. The (non-Affine) particle displacement field during these events have complex real space structure with multiple disconnected cores of high displacement appearing at the \emph{same} applied strain under athermal quasistatic simple shear deformation, and identified by a ``cell based cluster analysis'' method. By monitoring the stress relaxation during the first plastic event by Langevin dynamics simulation, we directly show the cascade nature of these events. Thus these first plastic events are reminiscent of avalanches in the post-yielding steady state, but unlike the steady state avalanches, we show that these events are not system spanning. To understand the nature of these events, we tune three factors that are known to affect brittleness of a glass. These are (i) sample preparation history, (ii) inter-particle interactions and (iii) rigidity of the background matrix applying a ``soft matrix'' probe recently developed by some of us. In each case we show that such first plastic events are more probable in more ductile glasses. Our observations are consistent with the picture that more ductile materials are softer, implying that understanding the role of softness may be a promising route to develop microscopic quantifiers of brittleness and thus clarifying the physical origin of brittle-to-ductile transition.
title Cascade at local yield strain for silica and metallic glass
topic Soft Condensed Matter
Disordered Systems and Neural Networks
Statistical Mechanics
url https://arxiv.org/abs/2506.17129