EP0141760A1 - Verfahren zur Calciumbehandlung von Stahl zur Erhöhung der Kaltverformungsfähigkeit und zur Lenkung des Siliziumgehaltes - Google Patents

Verfahren zur Calciumbehandlung von Stahl zur Erhöhung der Kaltverformungsfähigkeit und zur Lenkung des Siliziumgehaltes Download PDF

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Publication number
EP0141760A1
EP0141760A1 EP84420156A EP84420156A EP0141760A1 EP 0141760 A1 EP0141760 A1 EP 0141760A1 EP 84420156 A EP84420156 A EP 84420156A EP 84420156 A EP84420156 A EP 84420156A EP 0141760 A1 EP0141760 A1 EP 0141760A1
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European Patent Office
Prior art keywords
calcium
steel
cored wire
envelope
silicon
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Application number
EP84420156A
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English (en)
French (fr)
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EP0141760B1 (de
EP0141760B2 (de
Inventor
André Gueussier
Edmond Vachiery
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Vallourec SA
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Vallourec SA
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Application filed by Vallourec SA filed Critical Vallourec SA
Priority to AT84420156T priority Critical patent/ATE26307T1/de
Publication of EP0141760A1 publication Critical patent/EP0141760A1/de
Publication of EP0141760B1 publication Critical patent/EP0141760B1/de
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    • 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
    • C21C7/0056—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using cored wires
    • 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
    • C21C7/06—Deoxidising, e.g. killing
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
    • C22B9/10—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals with refining or fluxing agents; Use of materials therefor, e.g. slagging or scorifying agents
    • C22B9/103—Methods of introduction of solid or liquid refining or fluxing agents

Definitions

  • the process which is the subject of the invention relates to steels whose inclusions, thanks to an appropriate treatment, remain globular after rolling which gives them in the state of use particularly advantageous properties such as a great ability to stamping or cold stamping.
  • the steels thus treated have improved properties in many fields: isotropy, ductility, machinability.
  • this addition of calcium makes the inclusions present in the liquid metal liquid and therefore avoids the risks of clogging of the continuous casting nozzles.
  • Such steels must have a very low silicon content.
  • the limit not to be exceeded is most often 20 to 30 thousandths percent of silicon.
  • the silico-calcium used contains approximately 30% of Ca, 60% of Si and 10% of Fe + various impurities.
  • the weight of this silico-calcium which must be introduced into the liquid steel to obtain the full effectiveness of the calcium is about 0.5 to 1.5 kg per tonne of liquid steel.
  • the process according to the invention consists in developing in a known manner a liquid steel with a very low silicon content and then in introducing into this liquid steel a cored wire, provided with an envelope usually made of steel, the core of which is a material. divided comprising at least two components.
  • the first of these components is metallic calcium in grains the content of particles smaller than the meshes of the 150 mesh sieve does not exceed 2 to 3% by weight of said component.
  • the second is silico-calcium containing in mass% Ca 25 to 35, Si 50 to 70, Fe and impurities 5 to 15.
  • the mass ratio K, in the divided material, between the first component and the second is between 0.1 and 3.
  • the liquid steel is worked up so that its silicon content, before introduction of the cored wire, is less than 5 thousandths percent by mass.
  • the cored wire advantageously comprises a core of divided material which is in the compacted state inside the envelope, the latter having at least two parallel flattened zones, facing one another.
  • the grain calcium used is obtained by the process which is the subject of international PCT application WO 81/01811.
  • This process consists of melting the starting calcium and then passing it in the divided state through a purification bath, then, after decanting, spraying it by passage through a vibrating orifice and finally solidifying the drops obtained in grains.
  • the process according to the invention most often applies to the production of non-alloyed or low-alloyed steels.
  • the process according to the invention makes it possible to carry out, in a particularly economical manner, calcium additions to a steel, at the desired concentration in order to obtain the globularization of the inclusions, while maintaining the silicon content below a limit level, generally fixed by a standard.
  • a steel is thus obtained which, while having the characteristics specific to steels treated with calcium, in particular good isotropy of mechanical properties and excellent machinability, also exhibits excellent aptitude for cold deformation and more particularly stamping.
  • the quantities of silicon that can be introduced into the steel are also determined without exceeding the maximum acceptable limit.
  • This limit is most often around 20 to 30 thousandths percent.
  • a liquid steel with a very low silicon content for example less than 5 thousandths percent
  • this silicon is introduced in the form of a common type of calcium calcium, containing approximately in mass% Si 60, Ca 30 and Fe + impurities 10, it can be seen that the total amount of calcium calcium to be introduced is from 250 to 500 g per tonne of liquid steel. The corresponding amount of calcium thus introduced is 75 to 150 g per ton. It is enough to mix the calcium calcium in grains with silico-calcium to reach the amount of total calcium to be introduced. We can thus minimize the cost of developing such steels.
  • the invention also relates to a cored wire for the treatment of steel baths comprising a metallic envelope inside which is enclosed a divided material based on calcium and silicon.
  • This divided material comprises at least two components, the first being metallic calcium in grains of which the content of particles smaller than the meshes of the sieve of 150 mesh does not exceed 2 to 3% by weight of said component, the second being of silico-calcium containing in% by mass Ca 25 to 35%, Si 50 to 70%, Fe and impurities 5 to 15%, the ratio K between the contents of the first and second components being between 0.1 and 3 and preferably 0, 3 and 2.
  • the envelope of the cored wire according to the invention is made of steel.
  • a particularly advantageous solution for producing the cored wire is constituted by a wire whose envelope has at least two flattened parallel zones opposite one another.
  • This figure gives the ordinate the enrichment of the metal with silicon by injecting the cored wire as a function of the average calcium content of the mixture used.
  • the divided matter is constituted respectively by 1.5-1 and 0.5 kg of silico-calcium without addition of pure calcium.
  • the corresponding quantities of silicon which will be introduced into the liquid steel are: 900 g-600 g and 300 g of silicon per ton.
  • the introduction yield of this silicon being practically 100% it is seen that these additions of silicon-calcium enrich the steel in silicon respectively at these points by 90, 60 and 30 thousandths percent.
  • Such enrichments are not acceptable if we want to limit the final silicon content to a level, for example, less than 30 thousandths percent or even less than 25 or 20 thousandths percent.
  • the curves in the figure show that it is possible, by moderate enrichment in pure calcium of the divided matter, to lower the silicon content to the desired level. It can be seen, for example, that a mixture of divided matter having a K ratio of 0.6, that is to say in which the mass of pure calcium is equal to 60% of the mass of silica- calcium, divides by three the enrichment in silicon all other things being equal. This mixture contains 56% of Ca instead of 30% in the case of silico-calcium alone, and the mass necessary to treat a tonne of liquid steel no longer represents 53.6% of the initial mass.
  • K ratio of which can vary as required between 0.1 and 3.
  • K ratios can vary as required between 0.1 and 3.
  • K ratios can vary as required between 0.1 and 3.
  • K ratios can vary as required between 0.2 and 2. It is preferable to seek the use of K ratios as low as possible according to the aim sought so as to minimize the cost of the addition.
  • Calming in the ladle is carried out with aluminum without the addition of ferro-silicon.
  • This steel is treated in the ladle with a basic slag consisting of a mixture of alumina lime and fluorine spatch with stirring by blowing argon through a porous plug placed in the bottom of the ladle.
  • the quantity of silico-calcium introduced is 1.2 kg (corresponding to 0.36 kg of calcium) per tonne of liquid steel.
  • the steel is poured into ingots which are then transformed into slabs.
  • a steel for drawing of the same grade is produced by the process according to the invention for which the specification imposes a silicon content of less than 0.020%.
  • a cored wire with a steel casing is then introduced into the liquid steel, the divided material of which is a mixture of silico-calcium of the same composition as for the first preparation, and of pure calcium in grains.
  • the ratio K is equal to 1.33, which corresponds to a divided material whose average calcium content is 70%.
  • the amount of total calcium added is the same as in the first case, that is to say 360 g / t of liquid steel to be treated.
  • the divided matter mixture contains 294 g of pure calcium in grains, 221 g of silico-calcium containing only 132 g of silicon.
  • the mass of mixture to be introduced is reduced to 515 g / t instead of 1200 g / t, which significantly reduces the length of the cored wire.
  • the steel obtained by the process according to the invention therefore conforms to the specification relating to the silicon content. It has a structure substantially isotropic, a very good drawing ability.
  • the invention makes it possible to determine in each case the optimal amounts of calcium and of silico-calcium to be used to obtain a drawing steel under the most economical conditions.
  • the invention applies particularly well to the continuous casting of steels.
  • the injection of the cored wire for the above treatment can be carried out either in a bag or in a distributor.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Continuous Casting (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Heat Treatment Of Steel (AREA)
  • Chemical Treatment Of Metals (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
EP84420156A 1983-09-20 1984-09-19 Verfahren zur Calciumbehandlung von Stahl zur Erhöhung der Kaltverformungsfähigkeit und zur Lenkung des Siliziumgehaltes Expired - Lifetime EP0141760B2 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT84420156T ATE26307T1 (de) 1983-09-20 1984-09-19 Verfahren zur calciumbehandlung von stahl zur erhoehung der kaltverformungsfaehigkeit und zur lenkung des siliziumgehaltes.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8315191A FR2552107B1 (fr) 1983-09-20 1983-09-20 Procede de traitement de l'acier par le calcium permettant d'obtenir une grande aptitude a la mise en forme a froid et une basse teneur en silicium
FR8315191 1983-09-20

Publications (3)

Publication Number Publication Date
EP0141760A1 true EP0141760A1 (de) 1985-05-15
EP0141760B1 EP0141760B1 (de) 1987-04-01
EP0141760B2 EP0141760B2 (de) 1990-10-03

Family

ID=9292497

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84420156A Expired - Lifetime EP0141760B2 (de) 1983-09-20 1984-09-19 Verfahren zur Calciumbehandlung von Stahl zur Erhöhung der Kaltverformungsfähigkeit und zur Lenkung des Siliziumgehaltes

Country Status (8)

Country Link
US (1) US4555265A (de)
EP (1) EP0141760B2 (de)
JP (1) JPS6089514A (de)
AT (1) ATE26307T1 (de)
CA (1) CA1227335A (de)
DE (1) DE3462926D1 (de)
ES (1) ES8607409A1 (de)
FR (1) FR2552107B1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7906747B2 (en) 2004-06-10 2011-03-15 Affival Cored wire

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2166550C2 (ru) * 1999-03-26 2001-05-10 Центральный научно-исследовательский институт черной металлургии им. И.П. Бардина Способ производства низкокремнистой стали
RU2156308C1 (ru) * 1999-07-07 2000-09-20 ОАО "Новолипецкий металлургический комбинат" Способ обработки стали в ковше
RU2201458C1 (ru) * 2002-06-04 2003-03-27 ООО "Сорби стил" Способ модифицирования стали
RU2465340C1 (ru) * 2011-07-08 2012-10-27 Открытое акционерное общество "Магнитогорский металлургический комбинат" Способ производства низкокремнистой стали
RU2495139C1 (ru) * 2012-05-14 2013-10-10 Открытое акционерное общество "Магнитогорский металлургический комбинат" Способ производства низкоуглеродистой стали
FR3006695A1 (fr) 2013-06-10 2014-12-12 Mourad Toumi Procede et dispositif de traitement d'un metal ou d'un alliage metallique en fusion par une substance additive
RU2532793C1 (ru) * 2013-10-03 2014-11-10 Открытое акционерное общество "Северский трубный завод" Смесь для обработки стали в ковше
RU2562849C1 (ru) * 2014-06-11 2015-09-10 Федеральное государственное бюджетное учреждение науки Институт металлургии Уральского отделения Российской академии наук (ИМЕТ УрО РАН) Шлаковая смесь для обработки стали в ковше
RU2607877C2 (ru) * 2015-06-10 2017-01-20 Открытое акционерное общество "Волжский трубный завод" Способ внепечной обработки стали
RU2735697C1 (ru) * 2020-03-24 2020-11-06 Федеральное государственное бюджетное учреждение науки Институт металлургии Уральского отделения Российской академии наук (ИМЕТ УрО РАН) Способ внепечной обработки стали в ковше

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LU58377A1 (de) * 1969-04-04 1969-07-16
FR2253835A1 (de) * 1973-12-10 1975-07-04 Metallurg Exoproducts Corp
US3915693A (en) * 1972-06-21 1975-10-28 Robert T C Rasmussen Process, structure and composition relating to master alloys in wire or rod form
FR2282480A1 (fr) * 1974-08-21 1976-03-19 Stahltec Ag Additif d'alliage destine a l'amelioration des proprietes mecaniques d'aciers non allies, faiblement allies et fortement allies, et procede pour sa mise en oeuvre
WO1981001811A1 (fr) 1979-12-21 1981-07-09 Extramet Sa Procede de fabrication de granules metalliques, produits obtenus et dispositif pour la mise en oeuvre de ce procede
EP0034994A1 (de) 1980-02-26 1981-09-02 VALLOUREC Société Anonyme dite. Zusammengesetztes Produkt mit einem rohrförmigen Wickel und einem Kern aus kompaktem pulverförmigen Material und Verfahren zu seiner Herstellung

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5133761A (ja) * 1974-09-17 1976-03-23 Saito Kosakusho Kk Surasutobearingureesu no atsushukuseikeihoho
US4094666A (en) * 1977-05-24 1978-06-13 Metal Research Corporation Method for refining molten iron and steels

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LU58377A1 (de) * 1969-04-04 1969-07-16
US3915693A (en) * 1972-06-21 1975-10-28 Robert T C Rasmussen Process, structure and composition relating to master alloys in wire or rod form
FR2253835A1 (de) * 1973-12-10 1975-07-04 Metallurg Exoproducts Corp
FR2282480A1 (fr) * 1974-08-21 1976-03-19 Stahltec Ag Additif d'alliage destine a l'amelioration des proprietes mecaniques d'aciers non allies, faiblement allies et fortement allies, et procede pour sa mise en oeuvre
WO1981001811A1 (fr) 1979-12-21 1981-07-09 Extramet Sa Procede de fabrication de granules metalliques, produits obtenus et dispositif pour la mise en oeuvre de ce procede
EP0034994A1 (de) 1980-02-26 1981-09-02 VALLOUREC Société Anonyme dite. Zusammengesetztes Produkt mit einem rohrförmigen Wickel und einem Kern aus kompaktem pulverförmigen Material und Verfahren zu seiner Herstellung

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
STAHL UND EISEN, vol. 100, no. 1, 14 janvier 1980, pages 20-29, D}sseldorf, DE; "Die Behandlung von Stahlschmelzen mit Calcium" *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7906747B2 (en) 2004-06-10 2011-03-15 Affival Cored wire

Also Published As

Publication number Publication date
JPH0341524B2 (de) 1991-06-24
FR2552107B1 (fr) 1985-12-20
US4555265A (en) 1985-11-26
ES536043A0 (es) 1986-05-16
FR2552107A1 (fr) 1985-03-22
CA1227335A (fr) 1987-09-29
JPS6089514A (ja) 1985-05-20
DE3462926D1 (en) 1987-05-07
EP0141760B1 (de) 1987-04-01
ATE26307T1 (de) 1987-04-15
EP0141760B2 (de) 1990-10-03
ES8607409A1 (es) 1986-05-16

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