Electromagnetic augmentation for casting of thin metal sheets

Patent · Sun Jan 01 00:00:00 EST 1989

OSTI ID:867027

Hull, John R ^[1]

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1. Hinsdale, IL

Thin metal sheets are cast by magnetically levitating molten metal deposited in a mold within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled by the water-cooled walls of the mold to form a solid metal sheet. A conducting shield is electrically coupled to the molten metal sheet to provide a return path for eddy currents induced in the metal sheet by the current in the AC conducting coils. In another embodiment, a DC conducting coil is coupled to the metal sheet for providing a direct current therein which interacts with the magnetic field to levitate the moving metal sheet. Levitation of the metal sheet in both molten and solid forms reduces its contact pressure with the mold walls while maintaining sufficient engagement therebetween to permit efficient conductive cooling by the mold through which a coolant fluid may be circulated. The magnetic fields associated with the currents in the aforementioned coils levitate the molten metal sheet while the mold provides for its lateral and vertical confinement. A leader sheet having electromagnetic characteristics similar to those of the molten metal sheet is used to start the casing process and precedes the molten metal sheet through the yoke/coil arrangement and mold and forms a continuous sheet therewith. The yoke/coil arrangement may be either U-shaped with a single racetrack coil or may be rectangular with a pair of spaced, facing bedstead coils.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• DOE Contract Number: W-31109-ENG-38
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4846255
• OSTI ID: 867027
• Country of Publication: United States
• Language: English

Related Subjects

electromagnetic
augmentation
casting
metal
sheets
cast
magnetically
levitating
molten
deposited
mold
ferromagnetic
yoke
conducting
coils
linearly
displacing
levitated
liquid
cooled
water-cooled
walls
form
solid
sheet
shield
electrically
coupled
provide
return
path
eddy
currents
induced
current
embodiment
dc
coil
providing
direct
therein
interacts
magnetic
field
levitate
moving
levitation
forms
reduces
contact
pressure
maintaining
sufficient
engagement
therebetween
permit
efficient
conductive
cooling
coolant
fluid
circulated
fields
associated
aforementioned
provides
lateral
vertical
confinement
leader
characteristics
similar
start
casing
process
precedes
arrangement
continuous
therewith
u-shaped
single
racetrack
rectangular
pair
spaced
facing
bedstead
conducting shield
return path
continuous sheet
solid form
metal sheets
characteristics similar
eddy current
direct current
molten metal
magnetic field
liquid metal
magnetic fields
metal sheet
eddy currents
solid metal
contact pressure
coolant fluid
magnetically levitated
metal deposited
electrically coupled
racetrack coil
moving metal
sheet therewith
single racetrack
bedstead coils
levitated liquid
leader sheet
maintaining sufficient
coil arrangement
currents induced
conducting coils
metal deposit
ferromagnetic yoke
facing bedstead
electromagnetic characteristics
magnetic characteristic
linearly displacing
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