GB2038367A - Controlling the aluminium content of continuously cast silicon steels - Google Patents
Controlling the aluminium content of continuously cast silicon steels Download PDFInfo
- Publication number
- GB2038367A GB2038367A GB7935155A GB7935155A GB2038367A GB 2038367 A GB2038367 A GB 2038367A GB 7935155 A GB7935155 A GB 7935155A GB 7935155 A GB7935155 A GB 7935155A GB 2038367 A GB2038367 A GB 2038367A
- Authority
- GB
- United Kingdom
- Prior art keywords
- aluminium
- slag
- silicon dioxide
- slab
- oxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/111—Treating the molten metal by using protecting powders
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/076—Use of slags or fluxes as treating agents
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Continuous Casting (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Manufacturing Of Steel Electrode Plates (AREA)
Abstract
A method for controlling the aluminium content of continuously cast slab for manufacturing grain- oriented electrical steel sheet and strip, comprises transferring molten steel prepared for continuous casting and containing, by weight, not more than 4.0% silicon and 0.01 to 0.08% aluminium and 0.01% to 0.06% sulphur to a ladle or other vessel, adjusting a slag principally comprising silicon dioxide, calcium oxide and aluminium oxide on the surface of the molten steel to maintain the weight ratio of aluminium oxide to silicon dioxide of the slag at not less than 0.25, and continuously casting the molten steel.
Description
SPECIFICATION
Method for continuously casting slab for manufacturing grain-oriented electrical steel sheet and strip
The present invention is concerned with a method for continuously manufacturing cast slab for use in the production of grain-oriented electrical steel sheet and strip.
More particularly, the present invention is concerned with a method for continuously manufacturing cast slab for use in the production of grain-oriented steel sheet or strip containing, by weight, not more than 4.0% of silicon and 0.01 to 0.08% of aluminium and 0.010.06% of sulphur wherein the aluminium content or the aluminium and the sulphur of the continuously cast slab does not vary in the direction of continuous casting.
As a consequence, in accordance with the method of the present invention, there is obtained a continuously cast slab which is substantially uniform in aluminium or aluminium and sulphur content throughout its length. When this slab is used to produce grain-oriented electrical steel sheet or strip, the product obtained is free from any variation or degradation of its magnetic characteristics in the longitudinal direction due to variation of the aluminium or aluminium and sulphur content thereof.
As is wel known, the continuous casting method has numerous advantages over the conventional ingot casting method and, therefor, has been adopted for manufacturing slab for use in the production of electrical steel sheet and strip.
A problem arises, however, when grain-oriented electrical steel sheet and strip containing aluminium are produced from continuously cast slab, as will be clear from the following.
When slab is manufactured by the continuous casting method, the last of the molten metal used in the casting operation does not leave the ladle (or other vessel) in which it is contained until casting is completed and this may be for as long as 100 minutes or more. In other words, a part of the molten steel used for casting remains in the ladle throughout the considerably long period of time during which the continuous casting process is carried out. When molten steel containing aluminium or aluminium and sulphur is retained in the ladle for a long period of time, the aluminium and the sulphur in the molten steel reacts with the slag covering its surface and, as a result, aluminium and sulphur are transferred into the slag as aluminium oxide and calcium sulphide and these cause local variations in the aluminium content of the molten metal.Thus, when molten metal having local variations in its aluminium content is cast into a slab, the slab obtained has a variable aluminium content in the direction of casting. If this slab is used to produce grain-oriented electrical steel sheet or strip, the product obtained will have highly unstable magnetic properties in the longitudinal direction. It has, therefore, been impossible to use continuously cast slab for industrially producing grain-oriented electrical steel sheet and strip of the type containing aluminium and having uniform magnetic characteristics in the longitudinal direction.
The object of the present invention is to provide a method for continuously casting slab for use in producing grain-oriented electrical steel sheet and strip having uniform magnetic characteristics in the longitudinal direction and, particularly, to provide a method for continuously casting a slab having a uniform aluminium content in the direction of casting.
Thus, according to the present invention, there is provided a method for continuously casting slab for manufacturing grain-oriented electrical steel sheet and strip, comprising transferring molten steel prepared for continuous casting and containing, by weight, not more than 4.0% silicon and 0.01 to 0.08% aluminium to a ladle or other vessel, adjusting a slag principally comprising silicon dioxide, calcium oxide and aluminium oxide on the surface of the molten steel to maintain the weight ratio of aluminium oxide to silicon dioxide of the slag at not less than 0.25, and continuously casting the molten steel.
For a better understanding of the present invention, reference will be made to the accompanying drawings, in which:
Fig. 1 is a graph showing the relationship in the continuous casting process between the aluminium content of a molten metal in a ladle (or other vessel) and the length of time from the start of the casting operation in the method according to the present invention and the conventional method; and
Fig. 2 is a graph showing the relationship between the aluminium content of a grain-oriented electrical steel sheet or strip and its magnetic properties.
It has already been mentioned that, in carrying out the continuous casting method, the molten metal used in the casting operation must, in part, be retained in a ladle or other vessel (referred to simply as a "ladle" hereinafter) for the long period of time required to complete the operation. If the molten metal contains aluminium, the aluminium reacts with the slag on the molten metal surface and passes into the siag as oxide. Thus, the aluminium content of the molten metal in the ladle will vary from place two place and decrease as a whole with the passage of time. This is represented graphically in Fig.
1 which shows how the aluminium content of molten metal contained in a ladle decreases with the passage of time from the start of a continuous casting operation. The gradual decrease of the aluminium content of the molten metal with the passage of time results in a gradual decrease, in the direction of casting, in the aluminium content of the slab produced by continuous casting from the molten metal.
Grain-oriented electrical steel sheet or strip produced from such a slab will, therefore, suffer from variation in its magnetic properties because of the variation in its aluminium content in the longitudinal direction.
Fig. 2 shows the effect of the aluminium content on the magnetic characteristics of grain-oriented electrical steel sheet and strip. From this Figure, it will be seen that non-uniformity in the aluminium content of steel sheet or strip in the longitudinal direction will cause non-uniformity in the magnetic characteristic thereof and that, in order to obtain steel sheet and strip with uniform magnetic characteristics in the longitudinal directions, it is necessary to maintain the aluminium content of the molten metal in the ladle at the time of casting the slab from which the steel sheet or strip is produced at a constant value from the beginning to the completion of the casting operation.
The above described circumstances also apply in the case of the sulphur content of the molten metal. Namely, the gradual decrease with time in the sulphur content of the molten metal results in a gradual decrease, in the direction of casting, in the sulphur content of the continuously cast slab. The grain-oriented electrical steel sheet produced from such a slab therefor suffers from variation in its magnetic properties because of the variation in, not only its aluminium content, but also its sulphur content, in the longitudinal direction.
We have discovered that, in continuously casting a slab for use in producing grain-oriented electrical steel sheet and strip from molten metal containing, by weight, not more than 4.0% silicon and 0.01 to 0.08% aluminium and 0.01 to 0.06% sulphur, a slab having a uniform aluminium content in the direction of casting can be continuously cast if, among the components of the slag covering the molten metal in the ladle (this slag being that accompanying the molten when it is transferred to the ladle from a steel-making furnace or a secondary steel-making furnace, such as a vacuum degassing furnace, having calcium oxide and other slag-forming agents added thereto as required, being constituted, by weight, mainly of 5 to 50% calcium oxide, 5 to 30% silicon dioxide and 1 to 30% ferrous oxide and ferric oxide (as total iron) and containing small amounts of aluminium oxide, magnesium oxide, manganese oxide, phosphorus pentoxide, etc.), the weight ratio of aluminium oxide to silicon dioxide is maintained at 0.25 or more and preferably from 0.6 to 3.0, throughout the continuous casting operation.
The weight ratio of aluminium oxide to silicon dioxide in the slag constituents is maintained at the above-mentioned value by the addition of aluminium oxide-containing material and/or silicon dioxidecontaining material to the slag.
Although it is advantageous to make this addition at the time that the molten metal is transferred to the ladle, there is no restriction whatsoever on the time of the addition.
The aluminium oxide-containing material to be added is preferably bauxite and particularly calcined bauxite but other aluminium oxide-containing materials, such as powdered alumina, can also be used.
Silica can be advantageously used as the silicon dioxide-containing material but other silicon dioxide-containing materials can also be used without giving rise to any problems.
Moreover, it is possible to avoid a decrease, in the aluminium and sulphur content of the molten metal effectively, if in addition to maintaining the above mentioned ratio of aluminium oxide/silicon dioxide, the ratio of calcium oxide to silicon dioxide (CaO/SiO2) is maintained at 0.25 or more, preferably between 0.6-2.0.
Furthermore, depending upon the circumstances, it is possible to avoid 9 decrease in the aluminium content of the molten metal even more effectively by additionally maintaining the weight ratio of aluminium oxide to calcium in the slag components to not less than 1.0 and preferably 1.0 to 2.0. The source of calcium oxide for this purpose can be, for example, calcined lime.
The molten metal transferred to a ladle and covered by slag adjusted, in accordance with the
method of the present invention, is continuously cast into continuous casting mould via a conventional
continuous casting tundish to produce a continuously cast slab. The slab obtained in this manner is free from variations in its aluminium or aluminium and sulphur content in the direction of casting and is substantially uniform throughout in its aluminium or aluminium and sulphur content. After the slab has
been cooled, it is cut into lengths appropriate for rolling and the cut lengths are used to produce grain
oriented electrical sheet or strip by conventional methods. The resulting product possesses uniform
magnetic characteristics in the longitudinal direction of the steel strip.
It is possible, by means of the method of the present invention, to control not only the aluminium
content of the molten metal but also the sulphur content thereof.
The following Examples are given for the purpose of illustrating the present invention: EXAMPLE 1
100 tons of molten steel containing, by weight, 0.047% carbon, 2.9% silicon and 0.27%
aluminium and 0.025% sulphur, the balance being iron and unavoidable impurities, was transferred to a
ladle from a converter in which it had been produced. At this time, calcined -bauxite was added in an
amount of 5 kg. per ton of steel to adjust the composition of the slag in the ladle to, by weight, 16.50% calcium oxide, 20.07% silicon dioxide and 55.85% aluminium oxide, the remainder being other
components. The weight ratio of aluminium oxide to silicon dioxide at this time was 2.78.
The molten steel covered by the slag of the above composition was cast into a mould via a tundish to produce a continuously cast slab having a thickness of 200 mm. The time from start to completion of casting was 110 minutes.
The aluminium content as sol aluminium of the molten steel in the ladle at different times in the course of casting is shown in the following Table 1:
TABLE 1
Immediately before Time from start of completion casting (min.) 20 40 60 80 105 of casting Analysed value of Sol Al (%) 0.027 0.027 0.027 0.027 0.027 0.026 EXAMPLE 2
100 tons of molten steel containing, by weight, 0.052% carbon, 3.2% silicon, 0.028% aluminium and 0.024% sulphur, the balance being iron and unavoidable impurities, was transferred to a ladle from a converter in which it had been produced.At the same time, to the ladle was added calcined bauxite in an amount of 2.8 kg. per ton of steel and quicklime in an amount of 2.8 kg. per ton of steel. By means of this addition, the composition of the slag in the ladle was adjusted, by weight, to 32.12% calcium oxide, 22.34% silicon dioxide and 37.04% aluminium oxide, the remainder being other components. The weight ratio of aluminium oxide to silicon dioxide and the weight ratio of aluminium oxide to calcium oxide at this time were both 1.15.
The molten steel covered by the slag of the above composition was cast into a mould via a tundish to produce a continuously cast slab having a thickness of 200 mm. The time from start to completion of the casting was 110 minutes.
The aluminium content as sol aluminium of the molten steel in the ladle at different times in the course of casting is shown in the following Table 2:
TABLE 2
Immediately before Time from start of completion casting (min.) 20 40 60 80 105 of casting . ~ Analysed value of Sol Al (%) 0.028 0.027 0.028 0.027 0.026 0.027 EXAMPLE 3
100 tons of molten steel containing, by weight, 0.045% carbon, 2.9% silicon, 0.029% aluminium and 0.026% sulphur, the balance being iron and unavoidable impurities, was transferred to a ladle from a converter in which it had been produced.At the same time, calcined bauxite was added to the ladle in an amount of 5 kg. per ton of steel to adjust the composition of the slag in the ladle to, by weight, 28% calcium oxide, 31% silicon dioxide and 32% aluminium oxide, the remaining 9% being other components. The ratio of aluminium oxide to silicon dioxide at this time was 1.0.
The molten steel covered by the slag of the above composition was cast into a mould via a tundish to produce 11 continuously cast slabs with a thickness of 200 mm. The slabs were designated No. 1 to No. 11 in the order of their production.
Each of these slabs was heated to 13600 C. and rolled to give a 2.3 mm thick, hot rolled steel sheet which was thereafter annealed at 11 000C. and then cold rolled to give a steel sheet of 0.30 mm.
thickness. This cold rolled sheet was annealed at 8500C. and then subjected to secondary recrystallisation annealing at 1 2000C. to give a grain-oriented electrical steel sheet.
The aluminium and sulphur content of the eleven slabs and the magnetic characteristics in the longitudinal direction of the grain-oriented electrical sheet products obtained therefrom are shown in the following Table 3:
TABLE 3
Slab No. 1 - 8 9 10 11 Al content of hot rolled sheet 0.029% 0.028% 0.029% 0.029% S content of hot rolled sheet 0.026% 0.026% 0.026% 0.026% B10 of product 1.93T 1.93T 1.92T 1.92T W17 /50 of product 1.lOW/kg 1.07W/kg 1.08W/kg 1.12W/kg COMPARATIVE EXAMPLE
100 tons of molten steel containing, by weight,0.047% carbon, 2.9% silica, 0.026% aluminium and 0.026% sulphur, the balance being iron and unavoidable impurities, was transferred to a ladle from a converter in which it had been produced. The composition of the slag at the time was, by weight, 30% calcium oxide, 23% silicon dioxide, 4% aluminium oxide and 43% of other components: no adjustment of this composition was carried out. The ratio of aluminium oxide to silicon dioxide at this time was 0.17.
The molten steel covered by the slag of the above composition was cast into a mould via a tundish to produce 11 continuously cast slabs with a thickness of 200 mm. The slabs were numbered in the same way as those in Example 3.
The slabs were used to produce 0.30 mm. thick, grain-oriented electrical sheets by the same process as that described in Example 3.
The aluminium and sulphur content of the eleven slabs and the magnetic characteristics in the longitudinal direction of the grain-oriented electrical sheet products obtained therefrom are shown in the following Table 4.
TABLE 4
Slab No. 6 -- 7 8 -- 9 10 11 Al content of hot rolled sheet S content of hot rolled sheet 0.026% 0.025% 0.023% 0.022% 0.0220/o Boo of product 1.93T 1.92T 1.87T t.85T 1.85T W17/50 of product 1.OBW/kg 1.13W/kg 1.29W/kg 1.52W /kg 1.56W/kg It will be seen from Table 4 that the products produced from slab Silos. displayed good magnetic characteristics but that, since no adjustment was made in the composition of the slag in the manner according to the present invention, the aluminium and sulphur content of the slabs decreased gradually from slab No. 6 onward, with the result that there was a degradation in the magnetic characteristics of the products, which became particularly noticeable in the grain-oriented electrical sheets produced from the eighth and later slabs.
From the above Examples 1 to 3 and Comparative Example, it is clear that, when the molten steel prepared for continuous casting is covered by a slag, the composition of which is adjusted in accordance with the present invention, it is possible to produce continuously cast slab which is substantially free from variation in aluminium content and, if the circumstances so require, also in sulphur content in the direction of casting.
Claims (9)
1. A method for continuously casting slab for manufacturing grain-oriented electrical steel sheet and strip, comprising transferring molten steel prepared for continuous casting and containing, by weight, not more than 4.0% silicon and 0.01 to 0.08% aluminium and 0.01% to 0.06% sulphur to a ladle or other vessel, adjusting a slag principally comprising silicon dioxide, calcium oxide and aluminium oxide on the surface of the molten steel to maintain the weight ratio of aluminium oxide to silicon dioxide of the slag at not less than 0.25, and continuously casting the molten steel.
2. A method according to claim 1, wherein the weight ratio of aluminium oxide to silicon dioxide of the slag is maintained within the range of 0.6 to 3.0.
3. A method for continuously casting slab for manufacturing grain-oriented electrical steel sheet and strip, comprising transferring molten steel prepared for continuous casting and containing by weight not more than 4.0--0/0 silicon, 0.01-0.08-0/0 aluminium and 0.01-0.06-0/0 sulphur to a ladle or other vessel, adjusting a slag principally comprising silicon dioxide, calcium oxide and aluminium oxide on the surface of the molten steel to maintain the ratio of aluminium oxide to silicon dioxide and calcium oxide to silicon dioxide of the slag at no less than 0.25 respectively, and continuously casting the molten steel.
4. A method according to any of claims 1 to 3, wherein the weight ratio of aluminium oxide to calcium oxide of the slag is maintained at not less than 1.0.
5. A method according to claim 4, in which the weight ratio of aluminium oxide to calcium oxide of the slag is maintained with the range of 1.0 to 2.0.
6. A method according to claim 3, in which the ratio of calcium oxide to silicon dioxide of the slag is maintained within the range of 0.6 to 2.0.
7. A method according to claim 1 or claim 3 for continuously casting slab for manufacturing grainoriented electrical steel sheet and strip, substantially as hereinbefore described and exemplified.
8. Steel slab, whenever manufactured by the process according to the present invention.
9. Grain-oriented electrical steel sheet and strip, whenever produced from slab according to claim 8.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP53125590A JPS589125B2 (en) | 1978-10-12 | 1978-10-12 | Continuous casting method for unidirectional electrical steel |
| JP53130288A JPS5934207B2 (en) | 1978-10-23 | 1978-10-23 | Method for suppressing fluctuations in aluminum content in electrical steel sheets |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2038367A true GB2038367A (en) | 1980-07-23 |
| GB2038367B GB2038367B (en) | 1982-09-29 |
Family
ID=26461985
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7935155A Expired GB2038367B (en) | 1978-10-12 | 1979-10-10 | Controlling the aluminium content of continuously cast silicon steels |
Country Status (4)
| Country | Link |
|---|---|
| DE (1) | DE2941508C2 (en) |
| FR (1) | FR2438685A1 (en) |
| GB (1) | GB2038367B (en) |
| IT (1) | IT1164835B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1818420A1 (en) * | 2004-11-30 | 2007-08-15 | JFE Steel Corporation | Grain-oriented electromagnetic steel sheet and process for producing the same |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT399463B (en) * | 1987-03-03 | 1995-05-26 | Inteco Int Techn Beratung | METHOD FOR CONTINUOUSLY CASTING ELECTRIC STEEL AND ALLOYS |
| JPH01186253A (en) * | 1988-01-21 | 1989-07-25 | Nippon Steel Corp | Mold additive for continuous casting |
| DE10259335B4 (en) * | 2002-12-18 | 2005-04-14 | Refratechnik Holding Gmbh | Covering agent for a top slag, process for its preparation and use of the covering agent |
| DE10259826B4 (en) | 2002-12-19 | 2004-11-25 | Refratechnik Holding Gmbh | Coarse ceramic molded article, process for its production and use |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3727669A (en) * | 1970-05-19 | 1973-04-17 | Centro Speriment Metallurg | Process for continuous casting of steel for making grain-oriented electrical sheet in strip or sheets |
| DE2527553C3 (en) * | 1975-06-19 | 1978-08-10 | Mannesmann Ag, 4000 Duesseldorf | Molding powder for continuous and ingot casting |
-
1979
- 1979-10-10 GB GB7935155A patent/GB2038367B/en not_active Expired
- 1979-10-11 FR FR7925292A patent/FR2438685A1/en active Granted
- 1979-10-11 IT IT50538/79A patent/IT1164835B/en active
- 1979-10-12 DE DE2941508A patent/DE2941508C2/en not_active Expired
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1818420A1 (en) * | 2004-11-30 | 2007-08-15 | JFE Steel Corporation | Grain-oriented electromagnetic steel sheet and process for producing the same |
| EP1818420A4 (en) * | 2004-11-30 | 2011-04-06 | Jfe Steel Corp | Grain-oriented electromagnetic steel sheet and process for producing the same |
| US8177920B2 (en) | 2004-11-30 | 2012-05-15 | Jfe Steel Corporation | Grain-oriented electrical steel sheet and process for producing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2038367B (en) | 1982-09-29 |
| IT1164835B (en) | 1987-04-15 |
| FR2438685A1 (en) | 1980-05-09 |
| DE2941508C2 (en) | 1983-11-24 |
| DE2941508A1 (en) | 1980-04-30 |
| FR2438685B1 (en) | 1981-09-04 |
| IT7950538A0 (en) | 1979-10-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4979997A (en) | Process for producing grain-oriented electrical steel sheet having superior magnetic and surface film characteristics | |
| US5512110A (en) | Process for production of grain oriented electrical steel sheet having excellent magnetic properties | |
| US4944798A (en) | Method of manufacturing clean steel | |
| US4286984A (en) | Compositions and methods of production of alloy for treatment of liquid metals | |
| ES485101A1 (en) | Process for producing oriented silicon iron from strand cast slabs | |
| GB2038367A (en) | Controlling the aluminium content of continuously cast silicon steels | |
| US4006044A (en) | Steel slab containing silicon for use in electrical sheet and strip manufactured by continuous casting and method for manufacturing thereof | |
| US3522114A (en) | Production of steel for electrical sheet material | |
| US3992195A (en) | Process for the production of steel with increased ductility | |
| US4280837A (en) | Method for continuously casting slab for manufacturing grain-oriented electrical steel sheet and strip | |
| JP3994456B2 (en) | Method for producing steel for wire rods with excellent drawability and cleanliness | |
| JPS6241290B2 (en) | ||
| JPH05140649A (en) | Manufacture of now-oriented silicon steel sheet excellent in magnetic property | |
| JPS633007B2 (en) | ||
| US3986902A (en) | Silicon steel suitable for production of oriented silicon steel using low slab reheat temperature | |
| JPH07122090B2 (en) | Method of melting directional silicon steel material | |
| JP4653629B2 (en) | Method for producing Ti-containing chromium-containing molten steel | |
| US4067730A (en) | Process for the production of steel with increased ductility | |
| US4123258A (en) | Process for the production of steel with increased ductility and for the desulfurization of a steel melt | |
| US4978499A (en) | Soft steel for machine cutting and method of producing it | |
| US4853032A (en) | Process for producing low carbon steel for cold drawing | |
| JPS589125B2 (en) | Continuous casting method for unidirectional electrical steel | |
| KR100226931B1 (en) | Desulphurization method of degasing device | |
| JP7047818B2 (en) | Refining method of molten steel | |
| JPS6234801B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PE20 | Patent expired after termination of 20 years |
Effective date: 19991009 |