Hydrogen trapping in T24 steel weld joints – Microstructure influence vs. experimental design effect on activation energy for diffusion
- A common approach to describe hydrogen traps is by their activation energy that is necessary to release hydrogen from the trap. In the present study, Cr-Mo-V steel T24 (7CrMoVTiB10-10) base material and TIG weld metal were investigated. Electrochemically hydrogen charged specimens were analyzed by thermal desorption analysis (TDA) with different linear heating rates. The results show two different effects. At first, the microstructure effect on trapping is evident in terms of higher hydrogen concentrations in the weld metal and increased activation energy for hydrogen release. Secondly, it is necessary to monitor the real specimen temperature. A comparison between the adjusted heating rate and the real specimen temperature shows that the calculated activation energy varies by factor two. Thus, the trap character in case of the base material changes to irreversible at decreased temperature. Hence, the effect of the experimental procedure must be considered as well if evaluating TDAA common approach to describe hydrogen traps is by their activation energy that is necessary to release hydrogen from the trap. In the present study, Cr-Mo-V steel T24 (7CrMoVTiB10-10) base material and TIG weld metal were investigated. Electrochemically hydrogen charged specimens were analyzed by thermal desorption analysis (TDA) with different linear heating rates. The results show two different effects. At first, the microstructure effect on trapping is evident in terms of higher hydrogen concentrations in the weld metal and increased activation energy for hydrogen release. Secondly, it is necessary to monitor the real specimen temperature. A comparison between the adjusted heating rate and the real specimen temperature shows that the calculated activation energy varies by factor two. Thus, the trap character in case of the base material changes to irreversible at decreased temperature. Hence, the effect of the experimental procedure must be considered as well if evaluating TDA results.…
Autor*innen: | Michael RhodeORCiD |
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Dokumenttyp: | Vortrag |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2018 |
Organisationseinheit der BAM: | 9 Komponentensicherheit |
9 Komponentensicherheit / 9.0 Abteilungsleitung und andere | |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten | |
Freie Schlagwörter: | Creep-resisting materials; Diffusion; Hydrogen embrittlement; Weld metal |
Themenfelder/Aktivitätsfelder der BAM: | Chemie und Prozesstechnik |
Material | |
Veranstaltung: | Forschungsseminar Fügetechnik des IWF, Otto-von-Guericke-Universität |
Veranstaltungsort: | Magdeburg, Germany |
Beginndatum der Veranstaltung: | 25.04.2018 |
Enddatum der Veranstaltung: | 25.04.2018 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 14.05.2018 |
Referierte Publikation: | Nein |
Eingeladener Vortrag: | Nein |