Thermal activation and ductile vs. brittle behavior of microcracks in 3D BCC iron crystals under biaxial loading by atomistic simulations

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388998%3A_____%2F20%3A00536302" target="_blank" >RIV/61388998:_____/20:00536302 - isvavai.cz</a>

Result on the web

<a href="https://www.mdpi.com/2075-4701/10/11/1525" target="_blank" >https://www.mdpi.com/2075-4701/10/11/1525</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/met10111525" target="_blank" >10.3390/met10111525</a>

Result language

angličtina

Original language name

Thermal activation and ductile vs. brittle behavior of microcracks in 3D BCC iron crystals under biaxial loading by atomistic simulations

Original language description

We present the results of free 3D molecular dynamics (MD) simulations, focused on the influence of temperature on the ductile-brittle behavior of a pre-existing central Gri_th throughnmicrocrack (110)[110] (crack plane/crack front) under biaxial loading _A and _B in tension mode I. At temperatures of 300 K and 600 K, the MD results provide new information on the thresholdnvalues of the stress intensity factor K and the energy release rate G, needed for the emission of <111>{112} blunting dislocations that support crack stability. A simple procedure for the evaluation of thermal activation from MD results is proposed in the paper. 3D atomistic results are compared with continuum predictions on thermal activation of the crack induced dislocation generation. At elevatedntemperature T and biaxiality ratios _B/_A _ 0.8 dislocation emission in MD is observed, supported by thermal activation energy of about ~30 kBT.With increasing temperature, the ductile-brittle transition moves to a higher biaxiality ratios in comparison with the situation at temperature of ~0 K. Near the transition, dislocation emission occurs at lower loadings than expected by continuum predictions. For the ratios _B/_A _ 1, the elevated temperature facilitates (surprisingly) the microcrack growth below Gri_th level.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

20501 - Materials engineering

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2020

Confidentiality

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

Name of the periodical

Metals

ISSN

2075-4701

e-ISSN

—

Volume of the periodical

10

Issue of the periodical within the volume

11

Country of publishing house

CH - SWITZERLAND

Number of pages

27

Pages from-to

1525

UT code for WoS article

000594026400001

EID of the result in the Scopus database

2-s2.0-85096185768