Nanoscale stress distributions and microstructural changes at scratch track cross-sections of a deformed brittle-ductile CrN-Cr bilayer

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F20%3APU140156" target="_blank" >RIV/00216305:26620/20:PU140156 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1016/j.matdes.2020.109023" target="_blank" >https://doi.org/10.1016/j.matdes.2020.109023</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.matdes.2020.109023" target="_blank" >10.1016/j.matdes.2020.109023</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Nanoscale stress distributions and microstructural changes at scratch track cross-sections of a deformed brittle-ductile CrN-Cr bilayer

Popis výsledku v původním jazyce

In order to interpret the mechanical response of thin films subjected to scratch tests, it is necessary to elucidate local stress distributions and microstructural changes accompanying deformation across the scratch track area. Here, 50 nm synchrotron cross-sectional X-ray nanodiffraction and electron microscopy are used to characterize nanoscale multiaxial residual stress gradients and irreversible microstructural-morphological changes across a brittle-ductile film consisting of 1.2 and 2 mu m thick CrN and Cr sublayers. The experimental results reveal a complex alternation of the original columnar grain microstructure and a formation of pronounced lateral and depth stress gradients, which are complemented by a finite element model. After scratching, steep gradients of in plane, out-of-plane and shear stress distributions were revealed, ranging from -6 to 1.5 and - 1.5 to 1.5 GPa in CrN and Cr, respectively, which are furthermore correlated with microstructural changes and residual curvatures. The scratch test results in intergranular grain sliding and the formation of nanoscopic intragranular defects within CrN, while Cr sublayer's thickness reduction and pile-up formation are accompanied by a bending of columnar crystallites and localized plastic deformation. In summary, the quantitative stress data elucidate the stabilizing role of the Cr sublayer, which suppresses the bilayer's catastrophic fracture during scratch tests. (c) 2020 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Název v anglickém jazyce

Nanoscale stress distributions and microstructural changes at scratch track cross-sections of a deformed brittle-ductile CrN-Cr bilayer

Popis výsledku anglicky

In order to interpret the mechanical response of thin films subjected to scratch tests, it is necessary to elucidate local stress distributions and microstructural changes accompanying deformation across the scratch track area. Here, 50 nm synchrotron cross-sectional X-ray nanodiffraction and electron microscopy are used to characterize nanoscale multiaxial residual stress gradients and irreversible microstructural-morphological changes across a brittle-ductile film consisting of 1.2 and 2 mu m thick CrN and Cr sublayers. The experimental results reveal a complex alternation of the original columnar grain microstructure and a formation of pronounced lateral and depth stress gradients, which are complemented by a finite element model. After scratching, steep gradients of in plane, out-of-plane and shear stress distributions were revealed, ranging from -6 to 1.5 and - 1.5 to 1.5 GPa in CrN and Cr, respectively, which are furthermore correlated with microstructural changes and residual curvatures. The scratch test results in intergranular grain sliding and the formation of nanoscopic intragranular defects within CrN, while Cr sublayer's thickness reduction and pile-up formation are accompanied by a bending of columnar crystallites and localized plastic deformation. In summary, the quantitative stress data elucidate the stabilizing role of the Cr sublayer, which suppresses the bilayer's catastrophic fracture during scratch tests. (c) 2020 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

—

Návaznosti

—

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Materials & Design

ISSN

0264-1275

e-ISSN

1873-4197

Svazek periodika

195

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

16

Strana od-do

„109023-1“-„109023-16“

Kód UT WoS článku

000576531400005

EID výsledku v databázi Scopus

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