Open AccessInfluence of rotating magnetic field on the formation of solidification microstructure
Author(s) -
Chen Zhao,
Changle Chen,
Wen Xiao-li,
Jun Wen
Publication year - 2008
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.57.6277
Subject(s) - materials science , nucleation , microstructure , rotating magnetic field , intensity (physics) , lattice constant , condensed matter physics , alloy , magnetic field , eutectic system , grain size , diffraction , thermodynamics , composite material , optics , physics , quantum mechanics
The solidification microstructures of Pb-45%Sn hypoeutectic alloy in rotating magnetic field (RMF) were investigated. When the rotating frequency keeps constantthe grain size reduces linearly with the increase of magnetic intensityand structure of the primary phase changes from the dendrite to spherical crystals. X-ray diffraction (XRD) measurement indicates that the RMF causes the lattice expansion of primary phase (Pb)and the lattice parameter increases at first and then decreases with the increase of RMF intensity. Thereforethere is a critical value of magnetic intensity. Moreoverthe Sn content in primary phase (Pb)reduces gradually with the increase of magnetic intensity. The results are analyzed theoretically based on electromagnetism field theory and scattering law. It is revealed that RMF causes severe fluid flowand accelerates the diffusion of solute atom and heats the meltwhich results in the increase of nucleation rate and the decrease of growth velocity of crystal.