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Indexed by:期刊论文

Date of Publication:2015-03-01

Journal:INTERMETALLICS

Included Journals:SCIE、EI

Volume:58

Page Number:84-90

ISSN No.:0966-9795

Key Words:In situ; X-ray; Intermetallics; Crystal growth; Microstructure

Abstract:High resolution time-resolved X-ray imaging with synchrotron radiation has been used to in situ observe the growth behavior of Cu6Sn5 intermetallic compounds (IMCs) during solidification in Sn-6.5 Cu and Sn-6.5 Cu-0.2 Al (wt. %) solders under applied direct current (DC) field. The morphological evolution of Cu6Sn5 with I-like, X-like, Y-like and bird-like shapes is directly observed. It is shown that trace levels of Al have a marked effect on the solder microstructures and refining the size of the primary Cu6Sn5. The solidification pathway leading to the refinement is observed in real time using synchrotron microradiography. After adding the trace Al, I-like shapes bifurcate into X-like shapes. Furthermore, when DC field with 10 A/cm(2) is applied, both the growth rate and the mean size of Cu6Sn5 are increased but decreased when 100 A/cm(2) is applied. Meanwhile, the effect of thermodynamic potential barrier caused by DC field on the growth behavior of Cu6Sn5 is discussed. (C) 2014 Elsevier Ltd. All rights reserved.