Claims
- 1. A method for the continuous production of cast steel strands which are 200 mm.times.200 mm or less in cross-section by a continuous casting process in which molten steel containing over 0.20% of carbon is fed into a casting mold with a lubricant and continuously drawn out downwardly of the casting mold, said method comprising the steps of:
- (a) electromagnetically stirring the molten steel at a position within said casting mold by the application of a magnetic field induced by introducing into an electromagnetic coil an alterating current of a frequency (f) in the range of 1.5 to 15 Hz and maintaining the magnetic flux density in the range of 602 e.sup.-0.10 f to 1844 e.sup.-0.12f at the center of the electromagnetic coil, and
- (b) electromagnetically stirring the molten steel at a position in the final solidifying zone of said continuously cast strand in which the shorter diameter of the molten steel pool is smaller than 1/2 the length of the shorter side of the cast strand, by the application of a magnetic field induced by introducing an alternating current in the range of 50 to 60 Hz into an electromagnetic coil and maintaining the magnetic flux density in the range of 0.143.multidot.D.sup.2 +231 to 0.343.multidot.D.sup.2 +451 gauss at the center of the electromagnetic coil, wherein D is the solidified shell thickness in millimeters of said continuously cast strand, the value of D ranging from 20 to 90.
- 2. A method according to claim 1, which further comprises electromagneticaly stirring the molten steel at a position in the intermediate solidifying zone of said continuously cast strand by the application of a magnetic field induced by introducing an alternating current into an electromagnetic oil and maintaining the magnetic flux density in the range of 750000/(D-115).sup.2 to 750000/(D-86).sup.2 at the center of the electromagnetic coil, wherein D is the solidified shell thickness in millimeters of said continuously cast strand, the value of said D ranging from 10 to 50, and said intermediate solidifying zone being a zone between said casting mold and said final solidifying zone.
- 3. A method according to claim 1 or 2, wherein said lubricant further comprises oil.
- 4. A method according to claim 3, wherein said lubricant further comprises powder and said magnetic flux density (gauss) at the center of the electromagnetic coil in said casting mold is in the range of 602e.sup.-0.10f to 1339e.sup.-0.12 f.
- 5. A method according to claim 1, wherein said stirring in the final solidifying zone is carried out with an intermittent electric current or a periodically inverted polarity of an electric current.
- 6. A method according to claim 1 or claim 2, wherein said lubricant is a powder.
Priority Claims (4)
Number |
Date |
Country |
Kind |
55-43339 |
Apr 1980 |
JPX |
|
55-43340 |
Apr 1980 |
JPX |
|
55-43341 |
Apr 1980 |
JPX |
|
58-32068 |
Feb 1983 |
JPX |
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This application is a continuation of application Ser. No. 642,658, filed Aug. 21, 1984, now abandoned, which is a continuation-in-part application of our copending application Ser. No. 561,149 filed on Dec. 14, 1983, now U.S. Pat. No. 4,515,203, which is a continuation of application Ser. No. 250,041 filed on Apr. 1, 1981, now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
3656537 |
von Starck |
Apr 1972 |
|
4515203 |
Narita et al. |
May 1985 |
|
Continuations (2)
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Number |
Date |
Country |
Parent |
642658 |
Aug 1984 |
|
Parent |
250041 |
Apr 1981 |
|
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
561149 |
Dec 1983 |
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