EP0123632A1 - Verfahren zur Herstellung von Stählen mit hoher Zerspanbarkeit (Automatenstahl) - Google Patents
Verfahren zur Herstellung von Stählen mit hoher Zerspanbarkeit (Automatenstahl) Download PDFInfo
- Publication number
- EP0123632A1 EP0123632A1 EP84420046A EP84420046A EP0123632A1 EP 0123632 A1 EP0123632 A1 EP 0123632A1 EP 84420046 A EP84420046 A EP 84420046A EP 84420046 A EP84420046 A EP 84420046A EP 0123632 A1 EP0123632 A1 EP 0123632A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- sulfur
- calcium
- ppm
- steel
- carried out
- 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
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Classifications
-
- 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
- C21C7/064—Dephosphorising; Desulfurising
-
- 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
Definitions
- the process which is the subject of the invention relates to steels with high machinability.
- the high sulfur contents have no particularly favorable effect.
- the inclusions of oxides are particularly harmful, because they lead to wear of the cutting tool. It is possible to reduce the harmfulness of these inclusions by known means. We can, in particular, reduce the amount through good deoxidation and good decantation. We can also make these inclusions, generally alumina-based, globular by the addition of alkaline earth elements such as calcium, or other elements. We can finally arrange for these remaining globular inclusions to include a certain amount of combined sulfur which reduces its harmfulness.
- the sulfur content is generally not greater than that which is usually present in the steel, that is to say less than 500 ppm (parts per million by mass), and generally of the order from 150 to 500 ppm. In this interval, it is often sought to target a narrower sulfur content range, for a given use and grade, which presents serious difficulties.
- the treatment with aluminum is carried out to obtain a residual content of aluminum dissolved in the steel, between 150 and 500 ppm.
- the oxygen content is preferably lowered below 50 ppm and, preferably also, the desulfurization is carried out until a sulfur content of less than 50 ppm is obtained.
- the calcium and sulfur additions can be carried out either successively, the calcium being introduced first, or simultaneously.
- the addition of calcium is carried out by means of a cored wire advantageously containing a calcium alloy in grains or powder, such as a silico-calcium.
- the addition of sulfur is carried out by means of a cored wire advantageously containing flower of sulfur or a sulphide.
- cored wires may be used, or a single cored wire containing both calcium and sulfur in the desired proportions.
- the process makes it possible in particular to reproducibly obtain steels for which the difference between the sulfur content obtained and the targeted content does not exceed + 40 ppm.
- the process according to the invention makes it possible, thanks to the very precise additions of calcium and sulfur thus carried out, to obtain finely distributed globular inclusions which confer reproducible manner on steel, high machinability. These steels are particularly suitable for high speed machining using carbide cutting tools.
- the desulfurization is then carried out for example by means of a basic slag which can consist, for example, of lime or by an alumina-calcium composition.
- a basic slag which can consist, for example, of lime or by an alumina-calcium composition.
- the liquid metal must be stirred in contact with the slag, for example by blowing a neutral gas through this metal, or by any other means.
- the final sulfur and oxygen contents should preferably be less than 50 ppm for each of these elements.
- the calcium is then introduced into the liquid steel by means of a cored wire such as, for example, that which is described in FR 2,476,542.
- This wire consists of an envelope, generally made of mild steel, a few tenths of a mm thick, which surrounds the core which contains the calcium in the divided state in the form of metal or alloy.
- the introduction of the cored wire is preferably carried out at a relatively rapid speed in general of the order of 1 to a few meters per second. This speed is adjusted as a function of the content of the calcium-filled wire per unit of length and of the quantity to be introduced, so that the duration of this introduction does not exceed a few minutes.
- the wire is made to penetrate from top to bottom through the metal bath, at an angle preferably close to 90 ° relative to the horizontal.
- the amount of calcium thus introduced into the bath of liquid steel in the form of a metal or an alloy is preferably between 150 and 600 g / t, which allows, after reduction of the oxides still present in the metal, obtaining a calcium content preferably between 20 and 80 ppm.
- the liquid steel bath thus added with calcium is preferably homogenized by stirring before the addition of sulfur. This latter addition is carried out by means of a cored wire containing either sulfur in bloom or a sulphide such as iron or manganese sulphide, in pulverulent or granular form.
- the envelope is generally made of mild steel a few tenths of a mm thick, as in the case of the addition of calcium.
- the introduction of sulfur is carried out like that of calcium at relatively high speed.
- the steel is cast either in ingots or by means of a continuous casting installation. Maximum care must be taken to avoid reoxidation of the liquid steel jets during this casting operation.
- a light stirring of the liquid steel is maintained with argon for 3 minutes, after the end of the injection.
- the tubes thus obtained have machinability; using carbide cutting tools, much superior to that of common steels of the same composition.
- the duration in minutes on the abscissa along the axis T was shown for a frontal wear of tools of 0.4 mm and on the ordinate along the axis V the cutting speed in meters per minute.
- the curves A and B of the single figure thus give for each steel corresponding to the normalized state the cutting speed in meters per minute which allows a determined cutting time corresponding to a frontal wear of the tool of 0.4 mm.
- This is a dry run test carried out with an ISO-P30 carbide tool, the feed being 0.4 mm per revolution and the depth of the pass 2 mm.
- Example 2 The same steel as in Example 1 is produced under similar conditions, but by making the final additions of calcium and sulfur using a cored wire containing a mixture of flowers of sulfur and of calcium-calcium at 30% by mass of calcium.
- This mixture contains 20% sulfur and 80% silico-calcium. This cored wire weighs 170g per meter. It is introduced at 120 m per minute for 4 minutes, giving results similar to those of Example 1.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Heat Treatment Of Steel (AREA)
- Glass Compositions (AREA)
- Catalysts (AREA)
- Oxygen, Ozone, And Oxides In General (AREA)
- Powder Metallurgy (AREA)
- Heat Treatment Of Sheet Steel (AREA)
- Carbon And Carbon Compounds (AREA)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT84420046T ATE22705T1 (de) | 1983-03-15 | 1984-03-14 | Verfahren zur herstellung von staehlen mit hoher zerspanbarkeit (automatenstahl). |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8304611A FR2542761B1 (fr) | 1983-03-15 | 1983-03-15 | Procede de fabrication d'aciers a haute usinabilite |
FR8304611 | 1983-03-15 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0123632A1 true EP0123632A1 (de) | 1984-10-31 |
EP0123632B1 EP0123632B1 (de) | 1986-10-08 |
EP0123632B2 EP0123632B2 (de) | 1991-01-02 |
Family
ID=9287068
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP84420046A Expired - Lifetime EP0123632B2 (de) | 1983-03-15 | 1984-03-14 | Verfahren zur Herstellung von Stählen mit hoher Zerspanbarkeit (Automatenstahl) |
Country Status (10)
Country | Link |
---|---|
US (1) | US4531972A (de) |
EP (1) | EP0123632B2 (de) |
JP (1) | JPS59177347A (de) |
AT (1) | ATE22705T1 (de) |
CA (1) | CA1226737A (de) |
DE (1) | DE3460903D1 (de) |
ES (1) | ES8504945A1 (de) |
FR (1) | FR2542761B1 (de) |
MX (1) | MX160762A (de) |
ZA (1) | ZA841899B (de) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0316920A1 (de) * | 1987-11-19 | 1989-05-24 | SKW Trostberg Aktiengesellschaft | Stickstoffhaltiges Zusatzmittel für Stahlschmelzen |
AU593488B2 (en) * | 1987-04-03 | 1990-02-08 | Inland Steel Company | Controlling dissolved oxygen content in molten steel |
WO2005078142A1 (en) * | 2004-02-11 | 2005-08-25 | Tata Steel Limited | A cored wire injection process ih steel melts |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3939936A1 (de) * | 1989-12-02 | 1991-06-06 | Messerschmitt Boelkow Blohm | Steckverbindung zum elektrischen verbinden von leiterplatten |
US5397379A (en) * | 1993-09-22 | 1995-03-14 | Oglebay Norton Company | Process and additive for the ladle refining of steel |
US6179895B1 (en) | 1996-12-11 | 2001-01-30 | Performix Technologies, Ltd. | Basic tundish flux composition for steelmaking processes |
RU2465341C2 (ru) * | 2011-01-20 | 2012-10-27 | Открытое акционерное общество "Новолипецкий металлургический комбинат" | Способ обработки низкоуглеродистой стали в ковше |
RU2514125C1 (ru) * | 2012-11-30 | 2014-04-27 | Открытое акционерное общество "Магнитогорский металлургический комбинат" | Способ раскисления низкоуглеродистой стали |
RU2564373C1 (ru) * | 2014-07-10 | 2015-09-27 | Публичное акционерное общество "Северсталь" (ПАО "Северсталь") | Способ производства трубной стали |
RU2607877C2 (ru) * | 2015-06-10 | 2017-01-20 | Открытое акционерное общество "Волжский трубный завод" | Способ внепечной обработки стали |
RU2637194C1 (ru) * | 2016-11-22 | 2017-11-30 | Федеральное Государственное Унитарное Предприятие "Центральный научно-исследовательский институт черной металлургии им. И.П. Бардина" (ФГУП "ЦНИИчермет им. И.П. Бардина") | Способ ковшовой обработки легированных сталей |
RU2639080C1 (ru) * | 2016-12-28 | 2017-12-19 | Акционерное общество "Научно-производственное объединение "Центральный научно-исследовательский институт технологии машиностроения", АО "НПО "ЦНИИТМАШ" | Способ производства стали |
RU2708281C1 (ru) * | 2018-09-28 | 2019-12-05 | РЕЙЛ 1520 АйПи ЛТД | Способ внепечной обработки стали |
RU2686510C1 (ru) * | 2018-11-27 | 2019-04-29 | Акционерное общество "Выксунский металлургический завод" | Способ производства стали для изготовления труб |
RU2713770C1 (ru) * | 2019-05-31 | 2020-02-07 | Публичное акционерное общество "Трубная металлургическая компания" (ПАО "ТМК") | Способ производства стали с нормируемым содержанием серы |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4035892A (en) * | 1972-06-30 | 1977-07-19 | Tohei Ototani | Composite calcium clad material for treating molten metals |
FR2408661A1 (fr) * | 1977-09-15 | 1979-06-08 | British Steel Corp | Procede de production d'aciers resulfures |
US4235007A (en) * | 1975-07-25 | 1980-11-25 | Hitachi Cable, Ltd. | Method of production of a wire-shaped composite addition material |
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 |
US4373967A (en) * | 1979-04-09 | 1983-02-15 | Lukens, Inc. | Process for making resulfurized machinable steel |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3467167A (en) * | 1966-09-19 | 1969-09-16 | Kaiser Ind Corp | Process for continuously casting oxidizable metals |
GB1206062A (en) * | 1967-10-18 | 1970-09-23 | Nippon Kokan Kk | Deoxidation method |
DE1802991B2 (de) * | 1968-10-14 | 1972-02-17 | Süddeutsche Kalkstickstoff-Werke AG, 8223 Trostberg | Verwendung einer desoxydationslegierung zur herstellung von zumstranggiessen geeigneten stahlschmelzen |
US4057420A (en) * | 1976-02-06 | 1977-11-08 | Airco, Inc. | Methods for dissolving volatile addition agents in molten metal |
US4094666A (en) * | 1977-05-24 | 1978-06-13 | Metal Research Corporation | Method for refining molten iron and steels |
JPS5940202B2 (ja) * | 1979-12-20 | 1984-09-28 | 株式会社神戸製鋼所 | 極低s1快削鋼の製造方法 |
JPS56105460A (en) * | 1980-01-26 | 1981-08-21 | Nippon Steel Corp | Low-carbon low-sulfur free cutting steel and production thereof |
US4286984A (en) * | 1980-04-03 | 1981-09-01 | Luyckx Leon A | Compositions and methods of production of alloy for treatment of liquid metals |
JPS57134541A (en) * | 1981-02-16 | 1982-08-19 | Kawasaki Steel Corp | Manufacture of low-carbon sulfur free cutting steel |
-
1983
- 1983-03-15 FR FR8304611A patent/FR2542761B1/fr not_active Expired
- 1983-11-02 US US06/548,212 patent/US4531972A/en not_active Expired - Fee Related
-
1984
- 1984-03-13 JP JP59048010A patent/JPS59177347A/ja active Granted
- 1984-03-14 CA CA000449559A patent/CA1226737A/fr not_active Expired
- 1984-03-14 MX MX200670A patent/MX160762A/es unknown
- 1984-03-14 AT AT84420046T patent/ATE22705T1/de not_active IP Right Cessation
- 1984-03-14 ES ES530575A patent/ES8504945A1/es not_active Expired
- 1984-03-14 EP EP84420046A patent/EP0123632B2/de not_active Expired - Lifetime
- 1984-03-14 DE DE8484420046T patent/DE3460903D1/de not_active Expired
- 1984-03-14 ZA ZA841899A patent/ZA841899B/xx unknown
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4035892A (en) * | 1972-06-30 | 1977-07-19 | Tohei Ototani | Composite calcium clad material for treating molten metals |
US4235007A (en) * | 1975-07-25 | 1980-11-25 | Hitachi Cable, Ltd. | Method of production of a wire-shaped composite addition material |
FR2408661A1 (fr) * | 1977-09-15 | 1979-06-08 | British Steel Corp | Procede de production d'aciers resulfures |
US4373967A (en) * | 1979-04-09 | 1983-02-15 | Lukens, Inc. | Process for making resulfurized machinable steel |
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 (2)
Title |
---|
METALS ABSTRACTS, vol. 12, juin 1979, page 125, résumé no. 45-0249, Londres, GB; T. FUGIWARA et al.: "Development of calcium deoxidized free-machining steels" & RESEARCH AND DEVELOPMENT IN JAPAN, 1978, Tokyo, JP * |
REVUE DE METALLURGIE, vol. 74, no. 12, décembre 1977, pages 673-683, Paris, FR; J.C. BRUNET et al.: "Aciers de construction au calcium à usinabilité améliorée" * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU593488B2 (en) * | 1987-04-03 | 1990-02-08 | Inland Steel Company | Controlling dissolved oxygen content in molten steel |
EP0316920A1 (de) * | 1987-11-19 | 1989-05-24 | SKW Trostberg Aktiengesellschaft | Stickstoffhaltiges Zusatzmittel für Stahlschmelzen |
US4897114A (en) * | 1987-11-19 | 1990-01-30 | Skw Trostberg Aktiengesellschaft | Nitrogen-containing additive for steel melts |
WO2005078142A1 (en) * | 2004-02-11 | 2005-08-25 | Tata Steel Limited | A cored wire injection process ih steel melts |
US7682418B2 (en) | 2004-02-11 | 2010-03-23 | Tata Steel Limited | Cored wire injection process in steel melts |
Also Published As
Publication number | Publication date |
---|---|
JPH0368099B2 (de) | 1991-10-25 |
JPS59177347A (ja) | 1984-10-08 |
EP0123632B2 (de) | 1991-01-02 |
FR2542761A1 (fr) | 1984-09-21 |
ES530575A0 (es) | 1985-04-16 |
FR2542761B1 (fr) | 1987-10-16 |
ATE22705T1 (de) | 1986-10-15 |
CA1226737A (fr) | 1987-09-15 |
EP0123632B1 (de) | 1986-10-08 |
US4531972A (en) | 1985-07-30 |
ZA841899B (en) | 1984-10-31 |
MX160762A (es) | 1990-05-09 |
ES8504945A1 (es) | 1985-04-16 |
DE3460903D1 (en) | 1986-11-13 |
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