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Dynamic Magnetic Field Applications for Materials ProcessingMagnetic fields, variable in time and space, can be used to control convection in electrically conducting melts. Flow induced by these fields has been found to be beneficial for crystal growth applications. It allows increased crystal growth rates, and improves homogeneity and quality. Particularly beneficial is the natural convection damping capability of alternating magnetic fields. One well-known example is the rotating magnetic field (RMF) configuration. RMF induces liquid motion consisting of a swirling basic flow and a meridional secondary flow. In addition to crystal growth applications, RMF can also be used for mixing non-homogeneous melts in continuous metal castings. These applied aspects have stimulated increasing research on RMF-induced fluid dynamics. A novel type of magnetic field configuration consisting of an axisymmetric magnetostatic wave, designated the traveling magnetic field (TMF), has been recently proposed. It induces a basic flow in the form of a single vortex. TMF may find use in crystal growth techniques such as the vertical Bridgman (VB), float zone (FZ), and the traveling heater method. In this review, both methods, RMF and TMF are presented. Our recent theoretical and experimental results include such topics as localized TMF, natural convection dumping using TMF in a vertical Bridgman configuration, the traveling heater method, and the Lorentz force induced by TMF as a function of frequency. Experimentally, alloy mixing results, with and without applied TMF, will be presented. Finally, advantages of the traveling magnetic field, in comparison to the more mature rotating magnetic field method, will be discussed.
Document ID
20020022336
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Mazuruk, K.
Grugel, Richard N.
Motakef, S.
Whitaker, Ann F.
Date Acquired
August 20, 2013
Publication Date
January 1, 2001
Subject Category
Environment Pollution
Meeting Information
Meeting: 13th American Conference on Crystal Growth and Epitaxy
Location: Burlington, VT
Country: United States
Start Date: August 13, 2001
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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