Thermal desorption analysis of hydrogen trapping in micro-alloyed high strength steels
- Hydrogen can have an extreme degradation effects in steels, particularly concerning the mechanical properties. These effects can lead to hydrogen assisted cracking in micro-alloyed high strength steels during fabrication and/or operation in industrial applications. The Carrier Gas Hot Extraction method, which functionally combines a mass spectrometer with a Thermal Desorption Analysis process, was used for the detection of ultra-low diffusible hydrogen concentrations in the material specimens. The work shows the interaction between hydrogen and lattice defects in different micro-alloyed materials and HAZ. These steels were prepared in a quenched and tempered condition and in a thermo-mechanically rolled condition. The trapping characteristics of two steel grades, S690QL and S700MC, were studied with respect to the activation energy dependent on carbon content and micro-alloying elements such as Ti, Nb, Mo, Cr and V. The two steel grades exhibited several types of traps: carbideHydrogen can have an extreme degradation effects in steels, particularly concerning the mechanical properties. These effects can lead to hydrogen assisted cracking in micro-alloyed high strength steels during fabrication and/or operation in industrial applications. The Carrier Gas Hot Extraction method, which functionally combines a mass spectrometer with a Thermal Desorption Analysis process, was used for the detection of ultra-low diffusible hydrogen concentrations in the material specimens. The work shows the interaction between hydrogen and lattice defects in different micro-alloyed materials and HAZ. These steels were prepared in a quenched and tempered condition and in a thermo-mechanically rolled condition. The trapping characteristics of two steel grades, S690QL and S700MC, were studied with respect to the activation energy dependent on carbon content and micro-alloying elements such as Ti, Nb, Mo, Cr and V. The two steel grades exhibited several types of traps: carbide formations, dislocations and/or grain boundaries were common, which can influence activation energy and hydrogen solubility. The type and dimension of inclusions or particles also affected the hydrogen trapping behavior. A decrease of carbon and specific alloying elements in MC steels led to a change in the activation energy binding the trapped hydrogen. This thermo-mechanically hot rolled steel revealed an increased interaction between hydrogen and precipitations. The higher carbon content in the quenched and tempered steel led to a higher interaction between hydrogen and iron carbide, specifically in the martensitic phase. Furthermore,the trapping behavior in HAZ showed a significant increase in activation energy, especially in the coarse grained microstructure.…
Autor*innen: | Enrico Steppan |
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Koautor*innen: | Philipp Mantzke, Thomas Kannengießer |
Dokumenttyp: | Vortrag |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2016 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten |
Freie Schlagwörter: | Thermo-mechanical Hydrogen embrittlement; Hydrogen trapping; Micro-alloyed high strength steels; Quenched and tempered; S690; S700; Thermal desorption analysis (TDA) |
Veranstaltung: | 69th IIW Annual Assembly and International Conference |
Veranstaltungsort: | Melbourne, Australia |
Beginndatum der Veranstaltung: | 10.07.2016 |
Enddatum der Veranstaltung: | 15.07.2016 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 23.03.2017 |
Referierte Publikation: | Nein |
Eingeladener Vortrag: | Nein |