Secondary hardening of homogeneous T24 welds after short-term annealing at 450 and 530oC

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27360%2F20%3A10247176" target="_blank" >RIV/61989100:27360/20:10247176 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.confer.cz/metal/2020/3507-secondary-hardening-of-homogeneous-t24-welds-after-short-term-annealing-at-450-and-530-0c" target="_blank" >https://www.confer.cz/metal/2020/3507-secondary-hardening-of-homogeneous-t24-welds-after-short-term-annealing-at-450-and-530-0c</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.37904/metal.2020.3507" target="_blank" >10.37904/metal.2020.3507</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Secondary hardening of homogeneous T24 welds after short-term annealing at 450 and 530oC

Popis výsledku v původním jazyce

The T24 steel grade has been frequently used for the construction of membrane walls in modern power plant boilers. This steel grade has been developed with the intention of welding without post weld heat treatment. However, commissioning of new units of power plants into service revealed many defects in homogeneous T24 welds. Several remedial measures have been proposed. One of them represents annealing of boilers before putting them into service at 450 oC.This paper deals with characterization of microhardness and microstructure of homogeneous peripheral butt T24 welds after annealing at 450 oC for 48 hours and subsequent annealing at 530 oC for 10 hours. The results revealed that annealing at 450 oC led to a further increase of hardness in overheated parts of heat affected zones of homogeneous T24 welds. Subsequent short-term annealing at temperature of 530 oC, which corresponded to the typical temperature of boilers commissioning, caused a significant effect of secondary hardening in overheated parts of heat affected zones of homogeneous T24 welds. TEM investigations were carried out in order to explain this effect.

Název v anglickém jazyce

Secondary hardening of homogeneous T24 welds after short-term annealing at 450 and 530oC

Popis výsledku anglicky

The T24 steel grade has been frequently used for the construction of membrane walls in modern power plant boilers. This steel grade has been developed with the intention of welding without post weld heat treatment. However, commissioning of new units of power plants into service revealed many defects in homogeneous T24 welds. Several remedial measures have been proposed. One of them represents annealing of boilers before putting them into service at 450 oC.This paper deals with characterization of microhardness and microstructure of homogeneous peripheral butt T24 welds after annealing at 450 oC for 48 hours and subsequent annealing at 530 oC for 10 hours. The results revealed that annealing at 450 oC led to a further increase of hardness in overheated parts of heat affected zones of homogeneous T24 welds. Subsequent short-term annealing at temperature of 530 oC, which corresponded to the typical temperature of boilers commissioning, caused a significant effect of secondary hardening in overheated parts of heat affected zones of homogeneous T24 welds. TEM investigations were carried out in order to explain this effect.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20500 - Materials engineering

Projekt

<a href="/cs/project/EF17_048%2F0007373" target="_blank" >EF17_048/0007373: Predikce poškození konstrukčních materiálů</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název statě ve sborníku

METAL 2020 : 29th International Conference on Metallurgy and Materials : conference proceedings : May 20-22, 2020, Brno, Czech Republic, EU

ISBN

978-80-87294-97-0

ISSN

2694-9296

e-ISSN

—

Počet stran výsledku

6

Strana od-do

481-486

Název nakladatele

Tanger

Místo vydání

Ostrava

Místo konání akce

Brno

Datum konání akce

20. 5. 2020

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

—