Stress-Strain Response and Fatigue Lifetime of EEQ-111 Superalloy in Cyclic Loading at High Temperatures

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F24%3A00582280" target="_blank" >RIV/68081723:_____/24:00582280 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.prostr.2023.12.016" target="_blank" >http://dx.doi.org/10.1016/j.prostr.2023.12.016</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.prostr.2023.12.016" target="_blank" >10.1016/j.prostr.2023.12.016</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Stress-Strain Response and Fatigue Lifetime of EEQ-111 Superalloy in Cyclic Loading at High Temperatures

Popis výsledku v původním jazyce

The material under investigation was polycrystalline Sulzer’s nickel-based superalloy EEQ-111 which is equivalent to the original nGTD-111 developed in the late 1970s. The EEQ-111 superalloy is typical with coarse polyhedral dendritic grains with an average ngrain size of (2.48 ± 0.87) mm. The microstructure consists of γ channels, a bimodal distribution of nano-sized coherent γ´ nprecipitates, γ/γ´ eutectic, and MC and M23C6 carbides. The proportion of casting defects in the material is minimal due to the napplication of hot isostatic pressing. Low cycle fatigue experiments were executed on solid cylindrical specimens with a gauge nlength and diameter of 15 mm and 6 mm, respectively. A symmetrical push-pull cycling under strain control mode was utilized at n800 °C and 900 °C using servo-hydraulic testing machine MTS 810. Hysteresis loops, fatigue hardening/softening curves, and nfatigue lifetime curves in Coffin-Manson, Basquin, and total strain amplitude representations were obtained. Analysis of fracture nsurfaces and secondary cracks from metallographic sections revealed the preferential initiation sites of fatigue cracks that are nindependent of temperature. In contrast, the fatigue crack propagation is purely transgranular at 800 °C, whereas a mix of ntransgranular and intergranular crack propagation can be found at 900 °C indicating grain boundary weakening.

Název v anglickém jazyce

Stress-Strain Response and Fatigue Lifetime of EEQ-111 Superalloy in Cyclic Loading at High Temperatures

Popis výsledku anglicky

The material under investigation was polycrystalline Sulzer’s nickel-based superalloy EEQ-111 which is equivalent to the original nGTD-111 developed in the late 1970s. The EEQ-111 superalloy is typical with coarse polyhedral dendritic grains with an average ngrain size of (2.48 ± 0.87) mm. The microstructure consists of γ channels, a bimodal distribution of nano-sized coherent γ´ nprecipitates, γ/γ´ eutectic, and MC and M23C6 carbides. The proportion of casting defects in the material is minimal due to the napplication of hot isostatic pressing. Low cycle fatigue experiments were executed on solid cylindrical specimens with a gauge nlength and diameter of 15 mm and 6 mm, respectively. A symmetrical push-pull cycling under strain control mode was utilized at n800 °C and 900 °C using servo-hydraulic testing machine MTS 810. Hysteresis loops, fatigue hardening/softening curves, and nfatigue lifetime curves in Coffin-Manson, Basquin, and total strain amplitude representations were obtained. Analysis of fracture nsurfaces and secondary cracks from metallographic sections revealed the preferential initiation sites of fatigue cracks that are nindependent of temperature. In contrast, the fatigue crack propagation is purely transgranular at 800 °C, whereas a mix of ntransgranular and intergranular crack propagation can be found at 900 °C indicating grain boundary weakening.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2024

Kód důvěrnosti údajů

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

Název statě ve sborníku

Procedia Structural Intergrity

ISBN

—

ISSN

2452-3216

e-ISSN

—

Počet stran výsledku

11

Strana od-do

154-164

Název nakladatele

Elsevier

Místo vydání

Amsterdam

Místo konání akce

London

Datum konání akce

12. 9. 2023

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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