Hits:

Indexed by:期刊论文

Date of Publication:2013-06-01

Journal:ACTA METALLURGICA SINICA-ENGLISH LETTERS

Included Journals:SCIE、EI

Volume:26

Issue:3

Page Number:345-351

ISSN No.:1006-7191

Key Words:Spiral magnetic field; Forced convection; Eutectic lamellar spacing; Sn-Pb alloy; Composition segregation

Abstract:The effect of spiral magnetic field (SMF) on the solidification process of Sn-20 wt.%Pb hypoeutectic alloy was studied in this work. The temperature distribution and the macrosegregation together with the eutectic lamellar spacing during solidification were measured under different magnetic fields. The results indicate that the compositions in the top and bottom portions of the sample are nearly the same and the segregation phenomenon is basically eliminated by SMF at an exciting current of 125 A. The morphology of the primary phase transforms from coarse dendrite to rosette or ellipsoidal equiaxed crystal and the spacing of the eutectic lamellar increases from 1.6 to 3.9 mu m when the exciting current increases from 0 to 125 A. Moreover, if the exciting current is high enough, the forced fluid flow caused by SMF will enhance the process of transition from lamellar eutectic structure to anomalous rod-like one.