Origin of variable propensity for anomalousnslip in body-centered cubic metals

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F22%3A00563341" target="_blank" >RIV/68081723:_____/22:00563341 - isvavai.cz</a>

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.1088/1361-651X/ac9b79" target="_blank" >https://iopscience.iop.org/article/10.1088/1361-651X/ac9b79</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1361-651X/ac9b79" target="_blank" >10.1088/1361-651X/ac9b79</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Origin of variable propensity for anomalousnslip in body-centered cubic metals

Popis výsledku v původním jazyce

Many transition metals crystalizing in the body-centered cubic (bcc) structurenexhibit anomalous slip on low-stressed {110} planes at low homologous tem peratures, which cannot be reconciled with the Schmid law. Specifically, fornuniaxial loading in the center of the [001] − [011] − [¯111] stereographic tri angle, this is manifested by 1/2[111] and 1/2[1¯1¯1] screw dislocations movingnon low-stressed (0¯11) planes. While the anomalous slip is often attributednto non-planar cores of 1/2⟨111⟩ screw dislocations or to the tendency forntheir networks to glide easily, it remains unclear why it dominates the plasticndeformation in some bcc metals, whereas it is weak or even absent in others.nUsing molecular statics simulations at 0 K, we demonstrate that the anomalousnslip in bcc metals is intimately linked with the stability of ⟨100⟩ screw junc tions between two intersecting 1/2⟨111⟩ screw dislocations under stress (fornexample, 1/2[111] and 1/2[1¯1¯1] screws giving rise to the [100] junction). Ournatomic-level studies show that in nearly all bcc metals of the 5th and 6th groupsnthese junctions cannot be broken by the applied stress and the three dislocationsncan only move on the common {110} plane (in the above example on the (0¯11)nplane). On the other hand, these junctions are found to be unstable in alkalinmetals, tantalum, and iron, where the application of stress results in unzippingnof the two dislocations and their further glide on the planes predicted for isol ated dislocations. These results also suggest that the experimentally observednincreased propensity for the anomalous slip in further stages of plastic deform ation may be explained by reduced curvatures of 1/2⟨111⟩ screw dislocationnin dense networks.

Název v anglickém jazyce

Origin of variable propensity for anomalousnslip in body-centered cubic metals

Popis výsledku anglicky

Many transition metals crystalizing in the body-centered cubic (bcc) structurenexhibit anomalous slip on low-stressed {110} planes at low homologous tem peratures, which cannot be reconciled with the Schmid law. Specifically, fornuniaxial loading in the center of the [001] − [011] − [¯111] stereographic tri angle, this is manifested by 1/2[111] and 1/2[1¯1¯1] screw dislocations movingnon low-stressed (0¯11) planes. While the anomalous slip is often attributednto non-planar cores of 1/2⟨111⟩ screw dislocations or to the tendency forntheir networks to glide easily, it remains unclear why it dominates the plasticndeformation in some bcc metals, whereas it is weak or even absent in others.nUsing molecular statics simulations at 0 K, we demonstrate that the anomalousnslip in bcc metals is intimately linked with the stability of ⟨100⟩ screw junc tions between two intersecting 1/2⟨111⟩ screw dislocations under stress (fornexample, 1/2[111] and 1/2[1¯1¯1] screws giving rise to the [100] junction). Ournatomic-level studies show that in nearly all bcc metals of the 5th and 6th groupsnthese junctions cannot be broken by the applied stress and the three dislocationsncan only move on the common {110} plane (in the above example on the (0¯11)nplane). On the other hand, these junctions are found to be unstable in alkalinmetals, tantalum, and iron, where the application of stress results in unzippingnof the two dislocations and their further glide on the planes predicted for isol ated dislocations. These results also suggest that the experimentally observednincreased propensity for the anomalous slip in further stages of plastic deform ation may be explained by reduced curvatures of 1/2⟨111⟩ screw dislocationnin dense networks.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

<a href="/cs/project/GA19-23411S" target="_blank" >GA19-23411S: Souhra plasticity a magnetismu v alfa-železe a chromu</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Modelling and Simulation in Materials Science and Engineering

ISSN

0965-0393

e-ISSN

1361-651X

Svazek periodika

30

Číslo periodika v rámci svazku

8

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

21

Strana od-do

085007

Kód UT WoS článku

000877320500001

EID výsledku v databázi Scopus

2-s2.0-85141664184