Herlach, D.M. (2013) Containerless Processing in the Study of Metastable Solids from Undercooled Melts. In: Materials Science Forum, 526, Seiten 21-27. Trans Tech Publications, Switzerland. 2013 International conference on Materials Engineeering for Advanced Technologies (ICMEAT 2013), 2013-12-31 - 2014-01-02, Brisbane, Australien. doi: 10.4028/www.scientific.net/AMM.526.21. ISBN 978-303571208-7. ISSN 0255-5476.
Dieses Archiv kann nicht den Volltext zur Verfügung stellen.
Offizielle URL: http://www.scientific.net/AMM.526.21
Kurzfassung
An undercooled melt possesses an enhanced free enthalpy that enables to crystallize metastable solids in competition with their stable counterparts. Crystal nucleation selects the crystallographic phase whereas the growth dynamics controls microstructure evolution. We apply containerless processing such as electromagnetic and electrostatic levitation to containerlesss undercool and solidify metallic melts. Heterogeneous nucleation on container-walls is completely avoided leading to large undercooling with the extra benefit that the freely suspended drop is direct accessible for in situ observation of crystallization far away from equilibrium. Results of investigations of maximum undercoolability on pure zirconium are presented showing the limit of maximum undercoolability set by the onset of homogeneous nucleation. Rapid dendrite growth is measured as a function of undercooling by a high-speed camera and analysed within extended theories of non-equilibrium solidification. In such both supersaturated solid solutions and disordered superlattice structure of intermetallics are formed at high growth velocities. A sharp interface theory of dendrite growth is capable to describe the non-equilibrium solidification phenomena during rapid crystallization of deeply undercooled melts.
elib-URL des Eintrags: | https://elib.dlr.de/87936/ | ||||
---|---|---|---|---|---|
Dokumentart: | Konferenzbeitrag (Vortrag) | ||||
Titel: | Containerless Processing in the Study of Metastable Solids from Undercooled Melts | ||||
Autoren: |
| ||||
Datum: | Dezember 2013 | ||||
Erschienen in: | Materials Science Forum | ||||
Open Access: | Nein | ||||
In SCOPUS: | Ja | ||||
In ISI Web of Science: | Ja | ||||
Band: | 526 | ||||
DOI: | 10.4028/www.scientific.net/AMM.526.21 | ||||
Seitenbereich: | Seiten 21-27 | ||||
Verlag: | Trans Tech Publications, Switzerland | ||||
ISSN: | 0255-5476 | ||||
ISBN: | 978-303571208-7 | ||||
Stichwörter: | Containerless processing; Undercooling; Crystal nucleation; Dendritic growth; Supersaturated alloys; Disorder trapping; Metastable solids. | ||||
Veranstaltungstitel: | 2013 International conference on Materials Engineeering for Advanced Technologies (ICMEAT 2013) | ||||
Veranstaltungsort: | Brisbane, Australien | ||||
Veranstaltungsart: | internationale Konferenz | ||||
Veranstaltungsbeginn: | 31 Dezember 2013 | ||||
Veranstaltungsende: | 2 Januar 2014 | ||||
DLR - Schwerpunkt: | Raumfahrt | ||||
DLR - Forschungsgebiet: | R FR - Forschung unter Weltraumbedingungen | ||||
Standort: | Köln-Porz | ||||
Institute & Einrichtungen: | Institut für Materialphysik im Weltraum > Wissenschaftliche Experimente |
Nur für Mitarbeiter des Archivs: Kontrollseite des Eintrags