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Indexed by:期刊论文

Date of Publication:2016-09-15

Journal:JOURNAL OF CRYSTAL GROWTH

Included Journals:SCIE、EI、Scopus

Volume:450

Page Number:91-95

ISSN No.:0022-0248

Key Words:Directional solidification; Convection; Traveling magnetic field; Synchrotron X-ray radiography; Dendritic growth; Sn-Pb alloy

Abstract:Synchrotron X-ray radiography was used to in situ study the solute distribution and the dendritic growth during the bottom-up solidification of Sn-50 wt%Pb alloy under a traveling magnetic field (TMF) for the first time. The buoyance driven evolution and motion of the plumes containing Sn-rich melt are directly observed in the solidification front before the application of TMF. A forced melt flow from left to right is induced with the application of TMF, which results in the redistribution of the solute concentration (facilitate the solute transportation and reduce the local fluctuations considerably) and the change of the dendrite morphologies (promote/suppress the growth of the secondary arms, remelting and fragmentation of dendrites). Meanwhile, the concentration variations of Sn around the solidification front are quantitatively analyzed through the extraction of gray level from sequenced X-ray images. (C) 2016 Elsevier B.V. All rights reserved.