Kobler, A. ; Kashiwar, A. ; Hahn, H. ; Kübel, C. (2013)
Combination of in situ straining and ACOM TEM: A novel method for analysis of plastic deformation of nanocrystalline metals.
In: Ultramicroscopy, 128
doi: 10.1016/j.ultramic.2012.12.019
Artikel, Bibliographie
Kurzbeschreibung (Abstract)
Nanocrystalline metals are expected to exhibit different deformation mechanisms when compared to their coarse grained counterparts because the dislocation storage capacity decreases and the grain boundary mediated processes become more pronounced with decreasing grain size. As a new approach to directly image and quantify the plastic deformation processes in nanocrystalline thin films, a combination of automated crystal orientation mapping in microprobe STEM mode with in situ straining inside a TEM was developed. ACOM-TEM closes the gap between EBSD and BF/DFTEM by providing full orientation maps with nanometer resolution. The novel combination with in situ straining provided for the first time the possibility to directly image and quantify the structural changes of all crystallites in the ensemble of a thin film at the nanometer scale during mechanical deformation. It was used to characterize the metallographic changes during tensile deformation of a nanocrystalline Au thin film prepared by magnetron sputtering. The investigation of the grain size, grain orientation and twinning on a global (grain average over a micron sized area) and local (assembly of selected grains) scale allowed for the development of an in depth picture of the deformation processes. Grain boundary motion and local grain rotation were two of the processes acting to dissipate the applied stress. Additionally, twinning/detwinning occurred simultaneously during straining. These processes, which occurred locally already in the micro-plastic regime, led to global grain growth starting at the transition to the macro-plastic deformation regime.
| Typ des Eintrags: | Artikel |
|---|---|
| Erschienen: | 2013 |
| Autor(en): | Kobler, A. ; Kashiwar, A. ; Hahn, H. ; Kübel, C. |
| Art des Eintrags: | Bibliographie |
| Titel: | Combination of in situ straining and ACOM TEM: A novel method for analysis of plastic deformation of nanocrystalline metals |
| Sprache: | Englisch |
| Publikationsjahr: | Mai 2013 |
| Verlag: | Elsevier Science Publishing |
| Titel der Zeitschrift, Zeitung oder Schriftenreihe: | Ultramicroscopy |
| Jahrgang/Volume einer Zeitschrift: | 128 |
| DOI: | 10.1016/j.ultramic.2012.12.019 |
| Kurzbeschreibung (Abstract): | Nanocrystalline metals are expected to exhibit different deformation mechanisms when compared to their coarse grained counterparts because the dislocation storage capacity decreases and the grain boundary mediated processes become more pronounced with decreasing grain size. As a new approach to directly image and quantify the plastic deformation processes in nanocrystalline thin films, a combination of automated crystal orientation mapping in microprobe STEM mode with in situ straining inside a TEM was developed. ACOM-TEM closes the gap between EBSD and BF/DFTEM by providing full orientation maps with nanometer resolution. The novel combination with in situ straining provided for the first time the possibility to directly image and quantify the structural changes of all crystallites in the ensemble of a thin film at the nanometer scale during mechanical deformation. It was used to characterize the metallographic changes during tensile deformation of a nanocrystalline Au thin film prepared by magnetron sputtering. The investigation of the grain size, grain orientation and twinning on a global (grain average over a micron sized area) and local (assembly of selected grains) scale allowed for the development of an in depth picture of the deformation processes. Grain boundary motion and local grain rotation were two of the processes acting to dissipate the applied stress. Additionally, twinning/detwinning occurred simultaneously during straining. These processes, which occurred locally already in the micro-plastic regime, led to global grain growth starting at the transition to the macro-plastic deformation regime. |
| Freie Schlagworte: | In situ straining, Nanocrystalline metals, STEM, ACOM-TEM, Quantitative crystallographic analysis, Deformation mechanism |
| Fachbereich(e)/-gebiet(e): | 11 Fachbereich Material- und Geowissenschaften > Materialwissenschaft > Gemeinschaftslabor Nanomaterialien 11 Fachbereich Material- und Geowissenschaften > Materialwissenschaft 11 Fachbereich Material- und Geowissenschaften |
| Hinterlegungsdatum: | 05 Feb 2014 08:55 |
| Letzte Änderung: | 05 Feb 2014 08:55 |
| PPN: | |
| Sponsoren: | Financial support by the German Science Foundation (DFG) as part of the research group FOR714 “Plastic deformation of nanocrystalline metals” and the Karlsruhe Nano Micro Facility (KNMF) is gratefully acknowledged. |
| Export: | |
| Suche nach Titel in: | TUfind oder in Google |
 |
Frage zum Eintrag |
Optionen (nur für Redakteure)
 |
Redaktionelle Details anzeigen |
Drucken
Impressum