Critical view on the creep modelling procedures

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F15%3A00472821" target="_blank" >RIV/68081723:_____/15:00472821 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.12693/APhysPolA.128.540" target="_blank" >http://dx.doi.org/10.12693/APhysPolA.128.540</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.12693/APhysPolA.128.540" target="_blank" >10.12693/APhysPolA.128.540</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Critical view on the creep modelling procedures

Popis výsledku v původním jazyce

Process of creep deformation is rather complex, consisting of many interconnected subprocesses, mainly: (i) the creep strain itself, based on dislocation mobility as well as grain boundary activity, (ii) development of dislocation substructure (work strengthening and dynamic recovery), (iii) development of phase structure (phase transformations, precipitation, particle coarsening, etc.), and (iv) nucleation and development of voids and microcracks, i.e. creep damage. The creep experiments are time consuming and expensive, moreover, it is not possible to make experiments under the service conditions of particular materials due to very slow creep strain, the process seems to be ideal field for computer modelling. The experimental data are obviously available for the steady conditions only, so the effects of varying conditions during startup or shutdown of the components can be described by modelling. The model of creep deformation is obviously based on the so-called "creep constitutive equation", which should describe the strain rate dependence on stress, temperature and some other variables. Nevertheless, the comprehensive physical description of all the above mentioned processes is still missing. This paper should illustrate the shortcomings of most "creep constitutive equations", confronting them to some experimental results on common structural materials under non-steady loading conditions.

Název v anglickém jazyce

Critical view on the creep modelling procedures

Popis výsledku anglicky

Process of creep deformation is rather complex, consisting of many interconnected subprocesses, mainly: (i) the creep strain itself, based on dislocation mobility as well as grain boundary activity, (ii) development of dislocation substructure (work strengthening and dynamic recovery), (iii) development of phase structure (phase transformations, precipitation, particle coarsening, etc.), and (iv) nucleation and development of voids and microcracks, i.e. creep damage. The creep experiments are time consuming and expensive, moreover, it is not possible to make experiments under the service conditions of particular materials due to very slow creep strain, the process seems to be ideal field for computer modelling. The experimental data are obviously available for the steady conditions only, so the effects of varying conditions during startup or shutdown of the components can be described by modelling. The model of creep deformation is obviously based on the so-called "creep constitutive equation", which should describe the strain rate dependence on stress, temperature and some other variables. Nevertheless, the comprehensive physical description of all the above mentioned processes is still missing. This paper should illustrate the shortcomings of most "creep constitutive equations", confronting them to some experimental results on common structural materials under non-steady loading conditions.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

JJ - Ostatní materiály

OECD FORD obor

—

Projekt

<a href="/cs/project/FR-TI4%2F406" target="_blank" >FR-TI4/406: Výzkum vlivu technologie svařování tlustostěnných trubek orbitální hlavou na jejich dlouhodobou životnost v podmínkách provozu moderních energetických bloků</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2015

Kód důvěrnosti údajů

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

Název periodika

Acta Physica Polonica. A

ISSN

0587-4246

e-ISSN

—

Svazek periodika

128

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

PL - Polská republika

Počet stran výsledku

3

Strana od-do

540-542

Kód UT WoS článku

000366357300018

EID výsledku v databázi Scopus

2-s2.0-84950302436