Název: Analysis of cyclic plasticity of fatigued nickel based superalloys at elevated temperatures
Autoři: Petrenec, Martin ; Tobiáš, Jiří ; Polák, Jaroslav ; Šmíd, Miroslav ; Chlupová, Alice ; Petráš, Roman
Typ dokumentu: Příspěvky z konference
Konference/Akce: International Colloquim Mechanical Fatigue of Materials - ICMFM /16./, Brno (CZ), 2012-09-24 / 2012-09-26
Rok: 2012
Jazyk: eng
Abstrakt: Cyclic strain controlled multiple step tests have been performed on cylindrical specimens of cast Inconel 738LC superalloy at 23 and 800 °C and Inconel 792-5A superalloy at 800 °C in laboratory atmosphere. The effect of temperature on the cyclic stress-strain response characterized by internal and effective cyclic stress components and on the dislocation arrangement has been studied. The evolution of the effective and internal stress components and effective elastic moduli were derived from the hysteresis loops analyzed according to the statistical theory of the hysteresis loop. Cyclic hardening/softening curves and shortened cyclic stress-strain curves were obtained at all temperatures in both superalloys. The shortened cyclic stress-strain curves (CSSCs) can be fitted by power law at all temperatures and for both materials. They are shifted to lower stresses with increasing temperature. The CSSC of Inconel 792-5A is shifted to higher stress amplitude in comparison with that of Inconel 738LC due to different number and type of precipitates. Observation of dislocation structures by TEM revealed cyclic strain localization into persistent slip bands. Cyclic stress-strain response is compared at all temperatures in both superalloys and discussed in relation to the changes of internal and effective stress components and microstructural parameters of the material. Higher stress response of the Inconel 792-5A than of the Inconel 738LC superalloy at 800°C is due to higher effective stresses of respective γ´ phases.
Klíčová slova: effective stress; internal stress; precipitates; superalloy
Číslo projektu: GAP204/11/1453 (CEP)
Poskytovatel projektu: GA ČR
Zdrojový dokument: Proceedings of the 16th International Colloquium Mechanical Fatigue of Materials, ISBN 978-80-87434-05-5

Instituce: Ústav fyziky materiálů AV ČR (web)
Informace o dostupnosti dokumentu: Dokument je dostupný v příslušném ústavu Akademie věd ČR.
Původní záznam: http://hdl.handle.net/11104/0216729

Trvalý odkaz NUŠL: http://www.nusl.cz/ntk/nusl-136083


Záznam je zařazen do těchto sbírek:
Věda a výzkum > AV ČR > Ústav fyziky materiálů
Konferenční materiály > Příspěvky z konference