EP0044183B1 - Agents de traitement métallurgique - Google Patents

Agents de traitement métallurgique Download PDF

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Publication number
EP0044183B1
EP0044183B1 EP81303066A EP81303066A EP0044183B1 EP 0044183 B1 EP0044183 B1 EP 0044183B1 EP 81303066 A EP81303066 A EP 81303066A EP 81303066 A EP81303066 A EP 81303066A EP 0044183 B1 EP0044183 B1 EP 0044183B1
Authority
EP
European Patent Office
Prior art keywords
tube
melt
metal
magnesium
melting point
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.)
Expired
Application number
EP81303066A
Other languages
German (de)
English (en)
Other versions
EP0044183A1 (fr
Inventor
Heinrich Comes
Friedhelm Demey
Edmund Fuchs
Helmut Jaunich
Josef Schiffarth
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Foseco International Ltd
Original Assignee
Foseco International Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Foseco International Ltd filed Critical Foseco International Ltd
Priority to AT81303066T priority Critical patent/ATE12260T1/de
Publication of EP0044183A1 publication Critical patent/EP0044183A1/fr
Application granted granted Critical
Publication of EP0044183B1 publication Critical patent/EP0044183B1/fr
Expired legal-status Critical Current

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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
    • C21C7/0056—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
    • C21C1/00—Refining of pig-iron; Cast iron
    • C21C1/02—Dephosphorising or 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
    • C21C1/00—Refining of pig-iron; Cast iron
    • C21C1/10—Making spheroidal graphite cast-iron
    • 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
    • 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
    • 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 invention concerns metallurgical treatment agents, in particular such agents in wire-like form, and their manufacture and use.
  • reactive metals e.g. magnesium
  • molten metals e.g. iron and steel
  • the reactive metals are generally of relatively low melting point in the sense that their melting points are substantially lower than the temperatures of the metallic melts to be treated and the boiling point may also be below the temperature of the melt to be treated.
  • the known wire-like treatment agents all have one or more disadvantages regarding their manufacture and/or use.
  • a method of making a wire-like treatment agent for metal melts comprises heating a metallic tube, introducing into the tube a melt having a temperature below the melting point of the metal of the tube and comprising calcium or magnesium and causing or allowing the tube and melt so to cool that the melt solidifies in the tube, the diameter of the tube is from 5 to 15 mm and its wall thickness is from 0.1 to 1 mm.
  • the method of the invention has the advantage of not requiring the reactive metal i.e. the calcium or magnesium used to be initially in any particular form.
  • the melt introduced into the tube may be made by melting, for example, megnesium in ingot form.
  • reactive metals as calcium and magnesium when in particulate form are hazardous to handle and transport and tend to become contaminated by reaction with astmospheric oxygen and moisture.
  • any method of providing a tube filled with particulate material tends to result in the material being relatively loosely packed and in non-uniform packing.
  • a relatively long and narrow tube can be completely and uniformly filled and without any need for a drawing operation.
  • the method of the invention has a particular advantage over any method involving forming a tube around the desired contents in that a preformed tube is used and so there is no need for equipment to form the tube around the contents. Furthermore, if a tube is formed around particulate material there is a risk that air and moisture may be trapped in the product whereas this can be avoided in the method of the invention.
  • the method of the invention has a yet further advantage over any method involving using a strip of metal to form a tube around the desired contents, in that any such method means that the matter forming the tube must have one or more joins, e.g. a longitudinal join, and possibly also an overlapped portion.
  • a join is a potential weakness that in use of the product could give rise to premature and non-uniform release of the reac: tive metal and an overlapped portion, because of the increased thickness of the tube in the area of overlap, is also liable to give rise to non-uniform release of the reactive metal.
  • the tube is preferably heated to a temperature in the range of 150°C below the melting point of the matter to be introduced into the tube to 150°C above that melting point.
  • the heating is preferably maintained throughout the introduction of the melt into the tube.
  • the tube is not heated to a temperature as high as the boiling point of the melt.
  • the heating of the tube can be effected by passing an electric current through it and instead of, or in addition to this, heating of the tube may be achieved by induction and/or in an oven.
  • the heating of the tube serves to prevent premature solidification of the melt in the tube and achieving this object can be further aided by heating the melt to be introduced into the tube to a temperature above the melting point of its ingredient(s).
  • the introduction of the melt into the tube is preferably achieved by connecting one end of the tube to a supply of the melt to be introduced and applying a vacuum to the other end of the tube.
  • the melt may be forced into the tube by an applied pressure of inert gas.
  • the introduction of the melt into the tube can be aided by use of a siphoning effect.
  • the product can be produced in very long continuous lengths e.g. 500 m.
  • the tube is preferably of iron or steel if the treatment agent is for treatment of ferrous metals. It is particularly preferred that the melt introduced into the tube should contain or consist of magnesium or a magnesium alloy.
  • a wire-like product of the invention is to be used in circumstances where the undesirable phenomena mentioned above might tend to occur, it is preferred to produce in the product, after the tube has been filled with the solidified melt comprising a reactive metal, a number of holes in the tube, these holes being uniformly disposed around the tube and along its length.
  • the holes which may be generally circular, preferably have a size in the range of 0.1 to 2 mm.
  • the holes may be produced by, for example, passing the filled tube between one or more pairs of spiked rollers.
  • a lubricant may be applied to the tube in connection with the making of the holes and an oily film may remain and serve to protect the reactive metal, exposed at the holes, from atmospheric attack.
  • the holes after the holes have been formed, they can be closed with a material which is readily removed in use but serves to prevent access of oxygen and moisture. Oils and waxes are suitable materials for this purpose.
  • the tube may be given a porous internal coating of refractory material before it is filled with the melt comprising the reactive metal.
  • the refractory coating if present preferably comprises one or more of carbon, zirconia, alumina and magnesia.
  • it may be given an internal coating of another metal desired to achieve an additional metallurgical reaction when the product is used. Examples of metals for providing such a coating include aluminium, cerium, zirconium, titanium, columbium, silicon and lead.
  • any magnesium or other highly volatile metal in the tube in the form of an alloy or mixture with another metal or other substance.
  • suitable materials to provide the contents of the tube include magnesium-calcium, magnesium-zirconium and magnesium-nickel alloys and mixtures of magnesium with aluminium or compounds, e.g. carbides, of metals such as calcium.
  • a wire-like product for introducing a treatment agent comprising a reactive metal into a metal melt comprises a solidified melt comprising a reactive metal encased in a preformed tube of metal of higher melting point than that of the reactive metal.
  • Preferred features of the product are as described above.
  • a yet further aspect of the invention comprises treating a melt of metal by feeding into the melt a product of the invention.
  • the purpose of the treatment may be to effect one or more of desulphurisation, deoxidation, inclusion modification and nodularisation.
  • the product of the invention is especially useful for treatment of ferrous metals, particularly iron.
  • a length of the wire-like product may be fed continuously into the metal melt to be treated and the feeding rate can readily be varied or otherwise controlled.
  • the wire-like product may be fed into the melt through a refractory tube, the outlet from which may be beneath the surface of the melt, or the product may be fed directly into the melt, in which case the product must be sufficiently rigid that it can be fed well below the surface of the melt and the casing must be such that the product does not disintegrate until a sufficient depth below the surface of the melt is reached.
  • a coiled length of steel tube 1 communicates at one end with an angled metal pipe 2, the free end of which dips below the surface of molten magnesium 3 contained in a metal vessel 4.
  • the end of the tube 1 remote from the vessel 4 opens into a chamber 5 provided with a suction pump V for applying a vacuum.
  • a source of electric direct current 6 is connected by a lead 7 to the metal vessel 4 and by a lead 8. via an adjustable resistance 9, to the end of the pipe 2 remote from the vessel 4.
  • the tube 1 is positioned in an oven 10 for heating the tube.
  • magnesium ingots are melted to provide the melt 3.
  • the tube 1 is heated in the oven 10 to a temperature of about the melting point of magnesium. Electric direct current from the source 6 is passed through the lead 8, the adjustable resistance 9, the pipe 2, the melt 3 (which is electrically conductive) and the lead 7 and serves to keep the melt 3 molten and to heat the pipe 2 to a temperature of about the melting point of magnesium.
  • the temperature of the tube 1 is maintained and vacuum applied by means of the pump V to fill the tube 1 with molten magnesium.
  • the heating of the tube 1 is then discontinued and the tube and melt allowed to cool and the magnesium thereby caused to solidify in the tube, which is then disconnected from the angled pipe 2 and chamber 5.
  • the use of the chamber 5 facilitates competely filling the tube 1 with the melt without any risk of any of the melt being drawn into the pump.
  • the wire-like product of which Figure 2 shows merely a short length comprises a preformed steel tube 1 and within that a core 11 of solidified molten magnesium. Through the steel tube 1 are uniformly distributed holes 12.
  • the product can be made by first heating the steel tube (having no holes) to a temperature of about the melting point of magnesium, introducing molten magnesium into the tube and allowing it to solidify there and then moving the tube through a device to create the holes 12.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Materials For Medical Uses (AREA)

Claims (8)

1. Procédé pour fabriquer un agent de traitement en forme de fil pour un métal en fusion, caractérisé par le chauffage d'un tube métallique (1), l'introduction, dans le tube (1) d'une masse fondue (3) ayant une température inférieure au point de fusion du métal du tube et comprenant du calcium ou du magnésium et le refroidissement libre ou forcé du tube (1) et de la masse fondue de façon que celle-ci se solidifie dans le tube (1), le diamètre du tube (1) étant de 5 à 15 mm et son épaisseur de paroi étant de 0,1 à 1 mm.
2. Procédé suivant la revendication 1, dans lequel le tube (1) est chauffé à une température de l'intervalle de 150°C au-dessous du point de fusion de la matière à introduire dans le tube (1) jusqu'à 150°C au-delà de ce point de fusion.
3. Procédé suivant la revendication 1 ou 2, dans lequel la masse fondue (3) est introduite dans le tube (1) par raccordement d'une extrémité du tube (1) à. une réserve de masse fondue (3) à introduire et par entretien d'une dépression à l'autre extrémité du tube.
4. Procédé suivant l'une quelconque des revendications 1 à 3, dans lequel, après que la masse s'est solidifiée dans le tube (1), dés trous (12) répartis uniformément sur le contour du tube (1) et sur sa longueur sont ménagés dans le tube (1 ).
5. Agent de traitement en forme de fil pour un métal en fusion, qui comprend une gaine métallique (1) entourant du calcium ou du magnésium (11) à point de fusion intérieur, caractérisé en ce que la gaine (1) est un tube (1) formé au préalable et le calcium ou le magnésium est présent à l'état . de masse fondue solidifiée dans le tube (1), le diamètre du tube (1) étant de 5 à 15 mm et son épaisseur de paroi étant de 0,1 à 1 mm.
6. Agent de traitement suivant la revendication 5, dans lequel le tube (1) est fait d'acier et le métal réactif (11) est le magnésium ou un alliage de magnésium.
7. Agent de traitement suivant la revendication 5 ou 6, dans lequel des trous (12) sont répartis uniformément sur le contour du tube et sur sa longueur.
8. Agent de traitement suivant la revendication 7, dans lequel les trous ont une dimension de l'intervalle de 0,1 à 2 mm.
EP81303066A 1980-07-09 1981-07-06 Agents de traitement métallurgique Expired EP0044183B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81303066T ATE12260T1 (de) 1980-07-09 1981-07-06 Metallurgische behandlungsmittel.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8022513 1980-07-09
GB8022513 1980-07-09

Publications (2)

Publication Number Publication Date
EP0044183A1 EP0044183A1 (fr) 1982-01-20
EP0044183B1 true EP0044183B1 (fr) 1985-03-20

Family

ID=10514653

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81303066A Expired EP0044183B1 (fr) 1980-07-09 1981-07-06 Agents de traitement métallurgique

Country Status (6)

Country Link
EP (1) EP0044183B1 (fr)
JP (1) JPS6059972B2 (fr)
AT (1) ATE12260T1 (fr)
AU (1) AU542367B2 (fr)
DE (1) DE3169368D1 (fr)
NO (1) NO812327L (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19827354A1 (de) * 1998-06-19 1999-12-23 Evertz Egon Kg Gmbh & Co Verfahren zum Legieren von Stählen
DE19916235A1 (de) * 1999-03-01 2000-09-07 Odermath Stahlwerkstechnik Fülldraht zur Behandlung von Schmelzen mittels Drahtinjektion

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6191310A (ja) * 1984-10-08 1986-05-09 Sumikin Yousetsubou Kk 金属の性質改善用添加ワイヤの製造方法
EP0190089B1 (fr) * 1985-01-24 1989-01-18 Vallourec Procédé de traitement de métaux liquides par fil fourre contenant du calcium
US6471742B2 (en) * 2001-01-22 2002-10-29 Oscar G. Dam Method for producing an improved charging stock for use in metallurgical processes
FR2871477B1 (fr) 2004-06-10 2006-09-29 Affival Sa Sa Fil fourre
RU2487174C2 (ru) * 2011-02-07 2013-07-10 Закрытое акционерное общество "ФЕРРОСПЛАВ" Способ обработки железоуглеродистого расплава и материал для его осуществления
CN108176844B (zh) * 2018-01-15 2019-07-05 山东钢铁股份有限公司 一种清理中间包上水口结瘤物的装置和方法
CN112404372B (zh) * 2020-11-20 2021-12-14 国铭铸管股份有限公司 一种球墨铸铁的包内控速旋流球化方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE974835C (de) * 1951-02-27 1961-05-10 Max Planck Inst Eisenforschung Verfahren zum Desoxydieren von Eisen- und Stahlschmelzen
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
DE2421743B2 (de) * 1974-05-06 1979-06-07 Ototani, Tohei, Sendai (Japan) Verfahren zum Herstellen eines stangenförmigen Desoxydations- und Entschwefelungsmittels für Eisen- oder Stahlschmelzen o.dgl
JPS5214511A (en) * 1975-07-25 1977-02-03 Hitachi Cable Ltd Process for producing a linear additive
US4163827A (en) * 1978-01-23 1979-08-07 Caterpillar Tractor Co. Method of making a wrapped innoculation rod suitable for modifying the composition of molten metals

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19827354A1 (de) * 1998-06-19 1999-12-23 Evertz Egon Kg Gmbh & Co Verfahren zum Legieren von Stählen
DE19916235A1 (de) * 1999-03-01 2000-09-07 Odermath Stahlwerkstechnik Fülldraht zur Behandlung von Schmelzen mittels Drahtinjektion
DE19916235C2 (de) * 1999-03-01 2001-03-08 Odermath Stahlwerkstechnik Fülldraht zur Behandlung von Schmelzen mittels Drahtinjektion

Also Published As

Publication number Publication date
NO812327L (no) 1982-01-11
DE3169368D1 (en) 1985-04-25
AU7283281A (en) 1982-01-14
JPS6059972B2 (ja) 1985-12-27
EP0044183A1 (fr) 1982-01-20
AU542367B2 (en) 1985-02-21
ATE12260T1 (de) 1985-04-15
JPS5741334A (en) 1982-03-08

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