On the stress and temperature dependence of low temperature and high stress shear creep in Ni-base single crystal superalloys

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F20%3A00534084" target="_blank" >RIV/68081723:_____/20:00534084 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0921509320310339?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0921509320310339?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.msea.2020.139961" target="_blank" >10.1016/j.msea.2020.139961</a>

Jazyk výsledku

angličtina

Název v původním jazyce

On the stress and temperature dependence of low temperature and high stress shear creep in Ni-base single crystal superalloys

Popis výsledku v původním jazyce

In the present work, we investigate the stress and temperature dependence of low-temperature (750 + 20 degrees C) and high-stress (300 + 20 MPa) shear creep of a Ni-base single crystal superalloy. From continuous isothermal experiments and stress and temperature change tests the stress exponent n and the apparent activation energy Q(app) of the phenomenological Sherby-Dorn equation were determined for the two macroscopic crystallographic shear systems (MCSS) [01 (1) over bar](111) and [11 (2) over bar] (111). The activation parameters of creep, the stress exponents and the apparent activation energies were identified as 16 and 620 kJ/mol (MCSS: [01 (1) over bar](111)) and 14 and 460 kJ/mol (MCSS: [11 (2) over bar] (111)). We show that during shear creep testing these phenomenological parameters do not change between the early (0.5-1% strain) and later stages of creep (4.5-5% strain), in contrast to what was observed for uniaxial tensile testing. The results are discussed in the light of what is known about stress and temperature dependencies of deformation rates in the creep literature and in view of the recent work by Burger et al., 2020, who combined shear creep testing with analytical transmission electron microscopy to identify the elementary deformation mechanism, which governs low temperature and high stress creep.

Název v anglickém jazyce

On the stress and temperature dependence of low temperature and high stress shear creep in Ni-base single crystal superalloys

Popis výsledku anglicky

In the present work, we investigate the stress and temperature dependence of low-temperature (750 + 20 degrees C) and high-stress (300 + 20 MPa) shear creep of a Ni-base single crystal superalloy. From continuous isothermal experiments and stress and temperature change tests the stress exponent n and the apparent activation energy Q(app) of the phenomenological Sherby-Dorn equation were determined for the two macroscopic crystallographic shear systems (MCSS) [01 (1) over bar](111) and [11 (2) over bar] (111). The activation parameters of creep, the stress exponents and the apparent activation energies were identified as 16 and 620 kJ/mol (MCSS: [01 (1) over bar](111)) and 14 and 460 kJ/mol (MCSS: [11 (2) over bar] (111)). We show that during shear creep testing these phenomenological parameters do not change between the early (0.5-1% strain) and later stages of creep (4.5-5% strain), in contrast to what was observed for uniaxial tensile testing. The results are discussed in the light of what is known about stress and temperature dependencies of deformation rates in the creep literature and in view of the recent work by Burger et al., 2020, who combined shear creep testing with analytical transmission electron microscopy to identify the elementary deformation mechanism, which governs low temperature and high stress creep.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

<a href="/cs/project/EF16_025%2F0007304" target="_blank" >EF16_025/0007304: Materiály s vnitřní architekturou strukturované pro aditivní technologie</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Materials Science and Engineering A-Structural materials

ISSN

0921-5093

e-ISSN

—

Svazek periodika

795

Číslo periodika v rámci svazku

SEP

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

10

Strana od-do

139961

Kód UT WoS článku

000573282500001

EID výsledku v databázi Scopus

2-s2.0-85088875133