• Treffer 5 von 17
Zurück zur Trefferliste

Hydrogen trapping in T24 steel weld joints - microstructure influence vs. experimental design effect on activation energy for diffusion

  • In general, hydrogen assisted cracking is a result of a critical combination of local microstructure, mechanical load and hydrogen concentration. In that connection, welded microstructures of low-alloyed creep-resistant steels can show different hydrogen trapping kinetics. That influences the adsorbed hydrogen concentration as well as the diffusion itself in terms of moderate or strong trapping. A common approach to describe trapping is by the activation energy that is necessary to release hydrogen from a specific trap site. In the present study, T24 base material and weld metal were investigated. For that purpose, electrochemically hydrogen charged specimens were analyzed by thermal desorption analysis(TDA) with linear heating using a mass spectrometer. The results showed a microstructure effect on hydrogen trapping kinetics at elevated temperatures. Additionally, it is necessary to monitor the specimen temperature. A comparison between idealized temperature profile and real specimenIn general, hydrogen assisted cracking is a result of a critical combination of local microstructure, mechanical load and hydrogen concentration. In that connection, welded microstructures of low-alloyed creep-resistant steels can show different hydrogen trapping kinetics. That influences the adsorbed hydrogen concentration as well as the diffusion itself in terms of moderate or strong trapping. A common approach to describe trapping is by the activation energy that is necessary to release hydrogen from a specific trap site. In the present study, T24 base material and weld metal were investigated. For that purpose, electrochemically hydrogen charged specimens were analyzed by thermal desorption analysis(TDA) with linear heating using a mass spectrometer. The results showed a microstructure effect on hydrogen trapping kinetics at elevated temperatures. Additionally, it is necessary to monitor the specimen temperature. A comparison between idealized temperature profile and real specimen temperature showed that the calculated activation energy varied up to a factor of two. Thus, the assigned trap character(moderate or strong) changed. In case of high temperature peaks, this effect could be more important compared to the microstructure effect itself.zeige mehrzeige weniger

Volltext Dateien herunterladen

  • IIW_T24_Diff_TDA_Annual_V02.pdf
    eng

Metadaten exportieren

Weitere Dienste

Teilen auf Twitter Suche bei Google Scholar
Metadaten
Autoren/innen:Michael Rhode
Koautoren/innen:Tobias Mente, Enrico Steppan, Joerg Steger, Thomas Kannengiesser
Dokumenttyp:Vortrag
Veröffentlichungsform:Präsentation
Sprache:Englisch
Jahr der Erstveröffentlichung:2017
Organisationseinheit der BAM:9 Komponentensicherheit
9 Komponentensicherheit / 9.4 Integrität von Schweißverbindungen
DDC-Klassifikation:Naturwissenschaften und Mathematik / Chemie / Analytische Chemie
Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten
Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Angewandte Physik
Freie Schlagwörter:Creep resisting materials; Experimental design; Hydrogen diffusion; Microstructure; Thermal desorption analysis; Welding
Themenfelder/Aktivitätsfelder der BAM:Energie
Material
Material / Degradation von Werkstoffen und Materialien
Analytical Sciences
Analytical Sciences / Qualitätssicherung
Veranstaltung:70th IIW Annual Assembly, Commission II-A
Veranstaltungsort:Shanghai, People's Republic of China
Beginndatum der Veranstaltung:25.06.2017
Enddatum der Veranstaltung:28.06.2017
Verfügbarkeit des Volltexts:Volltext-PDF im Netzwerk der BAM verfügbar ("Closed Access")
Datum der Freischaltung:11.07.2017
Referierte Publikation:Nein