Structural Stability of the SUPER304H Steel Used in Energetics

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21220%2F22%3A00354202" target="_blank" >RIV/68407700:21220/22:00354202 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.3390/ma15020455" target="_blank" >https://doi.org/10.3390/ma15020455</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/ma15020455" target="_blank" >10.3390/ma15020455</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Structural Stability of the SUPER304H Steel Used in Energetics

Popis výsledku v původním jazyce

This paper describes the influence of technological treatments (i.e., bending or welding) on the structural stability of SUPER304H austenitic steel used in reheaters and superheaters in fossil fuel power plants. Although the worldwide trend is transitioning to green power sources, the lifetime of existing power plants has to be prolonged until the transition is complete. Experimental material was tested in as-received state (straight tubes), bends, and homogeneous weld joints. Part of the specimens was solution-annealed after the technological operation. Afterwards, all the samples were thermally aged in furnace (650, 675 and 700 °C) for 7,560–20,000 h. For comparison, bent specimens were placed at experimental sites on an operating powerplant for 10,000+ hours. The long-term aging causes the formation of Cr-based carbides on the grain boundaries along with the Fe-Cr sigma phase. Combination of elevated temperature and residual stress accelerates formation of the sigma phase. This can be prevented by solution-annealing after bending. Mechanical properties were evaluated by Vickers hardness and tensile tests. The microstructure was observed using light optical microscopy (LOM) and scanning electron microscopy (SEM) with the energy-dispersive X-ray detector (EDXS). Electron backscatter diffraction (EBSD) and X-ray powder diffraction (XRPD) were used to characterize the brittle phases.

Název v anglickém jazyce

Structural Stability of the SUPER304H Steel Used in Energetics

Popis výsledku anglicky

This paper describes the influence of technological treatments (i.e., bending or welding) on the structural stability of SUPER304H austenitic steel used in reheaters and superheaters in fossil fuel power plants. Although the worldwide trend is transitioning to green power sources, the lifetime of existing power plants has to be prolonged until the transition is complete. Experimental material was tested in as-received state (straight tubes), bends, and homogeneous weld joints. Part of the specimens was solution-annealed after the technological operation. Afterwards, all the samples were thermally aged in furnace (650, 675 and 700 °C) for 7,560–20,000 h. For comparison, bent specimens were placed at experimental sites on an operating powerplant for 10,000+ hours. The long-term aging causes the formation of Cr-based carbides on the grain boundaries along with the Fe-Cr sigma phase. Combination of elevated temperature and residual stress accelerates formation of the sigma phase. This can be prevented by solution-annealing after bending. Mechanical properties were evaluated by Vickers hardness and tensile tests. The microstructure was observed using light optical microscopy (LOM) and scanning electron microscopy (SEM) with the energy-dispersive X-ray detector (EDXS). Electron backscatter diffraction (EBSD) and X-ray powder diffraction (XRPD) were used to characterize the brittle phases.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

<a href="/cs/project/FV40166" target="_blank" >FV40166: Hodnocení degradovaných ocelí pro stavbu turbín a přehříváků elektrárenských kotlů (pro potřebu predikce zbytkové životnosti a lokálních oprav)</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

Materials

ISSN

1996-1944

e-ISSN

1996-1944

Svazek periodika

15

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

19

Strana od-do

—

Kód UT WoS článku

000746160200001

EID výsledku v databázi Scopus

2-s2.0-85122248828