Dresden 2006 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

MM: Metall- und Materialphysik

MM 25: Poster Session

MM 25.17: Poster

Mittwoch, 29. März 2006, 15:30–17:30, P4

Dendritic solidification of metallic melts with ceramic particles — •Matthias Kolbe¹, Thomas Lierfeld^1,2, Phanikumar Gandham^1,3, Thomas Schenk^4,5, Gunther Eggeler², and Dieter M. Herlach¹ — ¹Institute for Space Simulation, DLR, Cologne, Germany — ²Institute of Materials, Ruhr-University Bochum, Germany — ³Department of Metallurgical and Materials Engineering, IITM, Chennai, India — ⁴Experiments Division (ID19), ESRF, Grenoble, France — ⁵Laboratoire de Physique des Matériaux, ÉdM de Nancy, France

The interaction of a dendritic solid/liquid interface with ceramic particles (Ni₉₈Ta₂ + Ta₂O₅) has been investigated by undercooling experiments at different levels of convection: (i) in a terrestrial electromagnetic levitation facility (EML) and (ii) in TEMPUS, a facility for containerless processing, under low gravity conditions during parabolic flights. Entrapment of particles in ground experiments and engulfment of a significant fraction of submicron particles under low gravity conditions are attributed to the lower level of convection in the latter experiments and to morphological features of dendritic solidification. Directional solidification of Al₉₀Cu₁₀ with alumina particles has been observed in-situ by X-ray radiography at ESRF. Tip splitting of Al-rich dendrites and evolution of cauliflower morphology has been observed. No evidence has been found for an influence of the alumina particles on dendrite growth.