Detail publikace
Initiation of fatigue cracks and lifetime of Ni-base superalloys at high mean stress and temperature
KUNZ, L. HORNÍK, V. HUTAŘ, P. FINTOVÁ, S.
Anglický název
Initiation of fatigue cracks and lifetime of Ni-base superalloys at high mean stress and temperature
Typ
článek v časopise - ostatní, Jost
Jazyk
en
Originální abstrakt
The effect of high-frequency cycling (120 Hz) superimposed on high tensile mean stress on a lifetime of cast Ni-base superalloys IN 713LC at 800 °C and MAR-M 247 at 900 °C was investigated. It has been found that both the alloys exhibit qualitatively similar behavior in creep/fatigue loading conditions. Superposition of small stress amplitudes on the tensile mean stress does not influence the time to fracture until the stress amplitude reaches a threshold value, which is dependent on the mean stress. The higher the mean stress the higher is the stress amplitude threshold value. The observed creep/fatigue behavior is governed by two mechanisms: (a) formation and growth of intergranular cracks by creep mechanism (b) initiation and growth of fatigue cracks from the intergranular creep cracks. The casting defects do not play any important role as regards the lifetime under investigated loading conditions.
Anglický abstrakt
The effect of high-frequency cycling (120 Hz) superimposed on high tensile mean stress on a lifetime of cast Ni-base superalloys IN 713LC at 800 °C and MAR-M 247 at 900 °C was investigated. It has been found that both the alloys exhibit qualitatively similar behavior in creep/fatigue loading conditions. Superposition of small stress amplitudes on the tensile mean stress does not influence the time to fracture until the stress amplitude reaches a threshold value, which is dependent on the mean stress. The higher the mean stress the higher is the stress amplitude threshold value. The observed creep/fatigue behavior is governed by two mechanisms: (a) formation and growth of intergranular cracks by creep mechanism (b) initiation and growth of fatigue cracks from the intergranular creep cracks. The casting defects do not play any important role as regards the lifetime under investigated loading conditions.
Klíčová slova anglicky
IN 713LC MAR-M247 creep/fatigue loading time to fracture defects
Vydáno
12.12.2017
Nakladatel
Elsevier Ltd
ISSN
2452-3216
Ročník
7
Číslo
1
Strany od–do
44–49
Počet stran
6
BIBTEX
@article{BUT152036,
author="Ludvík {Kunz} and Vít {Horník} and Pavel {Hutař} and Stanislava {Fintová},
title="Initiation of fatigue cracks and lifetime of Ni-base superalloys at high mean stress and temperature",
year="2017",
volume="7",
number="1",
month="December",
pages="44--49",
publisher="Elsevier Ltd",
issn="2452-3216"
}