Effects of temperature and strain rate on isothermal low-cycle fatigue behaviour of Inconel 718 superalloy: Damage mechanisms, microstructure evolution, and life prediction

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F25%3A00619415" target="_blank" >RIV/68081723:_____/25:00619415 - isvavai.cz</a>

Alternative codes found

RIV/68407700:21220/25:00384522

Result on the web

<a href="https://www.webofscience.com/wos/woscc/full-record/WOS:001488516100001" target="_blank" >https://www.webofscience.com/wos/woscc/full-record/WOS:001488516100001</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijfatigue.2025.109005" target="_blank" >10.1016/j.ijfatigue.2025.109005</a>

Result language

angličtina

Original language name

Effects of temperature and strain rate on isothermal low-cycle fatigue behaviour of Inconel 718 superalloy: Damage mechanisms, microstructure evolution, and life prediction

Original language description

In this article, strain-controlled Low-Cycle Fatigue (LCF) tests were performed on Inconel 718 nickel-based superalloy at temperatures of 300 ◦C, 650 ◦C, and 730 ◦C. The LCF tests were conducted at various mechanical strain amplitudes between 3.5×10−3 and 1×10−2, and three different mechanical strain rates: 1×10−4/s, 1×10−3/s, and 1×10−2/s. Cyclic straining resulted in cyclic softening under all investigated loading conditions, with the effect being more significant at higher temperatures. The cyclic softening was attributed to the formation of persistent slip bands and the shearing of coherent precipitates. At 730 ◦C, delta phase precipitation in LCF tests conducted at low strain rates contributed to additional softening. Investigations into the damage mechanisms revealed that the predominant failure mode shifted from transgranular at 300 ◦C to intergranular at 650 ◦C and 730 ◦C. In addition, fatigue crack initiation sites most frequently involved broken or oxidized carbides. The fatigue lifetime decreased with an increasing temperature and a decreasing strain rate, primarily due to oxidation-assisted intergranular cracking at high temperatures, involving the formation of brittle oxides at grain boundaries. Finally, a multi-mechanism-based damage model was proposed to predict fatigue lifetime, accounting for contributions from oxidation, creep, and fatigue damage. The model exhibited a good correlation between the predicted and the observed lifetimes.

Czech name

—

Czech description

—

Type

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

CEP classification

—

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

2025

Confidentiality

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

Name of the periodical

International Journal of Fatigue

ISSN

0142-1123

e-ISSN

1879-3452

Volume of the periodical

198

Issue of the periodical within the volume

Sept

Country of publishing house

GB - UNITED KINGDOM

Number of pages

19

Pages from-to

109005

UT code for WoS article

001488516100001

EID of the result in the Scopus database

2-s2.0-105003995909