EP0044183A1 - Metallurgische Behandlungsmittel - Google Patents
Metallurgische Behandlungsmittel Download PDFInfo
- Publication number
- EP0044183A1 EP0044183A1 EP81303066A EP81303066A EP0044183A1 EP 0044183 A1 EP0044183 A1 EP 0044183A1 EP 81303066 A EP81303066 A EP 81303066A EP 81303066 A EP81303066 A EP 81303066A EP 0044183 A1 EP0044183 A1 EP 0044183A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- tube
- melt
- metal
- magnesium
- treatment agent
- 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
Images
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 a reactive metal and causing or allowing the tube and melt so to cool that the melt solidifies in the tube.
- the method of the invention has the advantage of not requiring the reactive metal used to be initially in any particular form.
- the melt introduced into the tube may be made by melting, for example, magnesium 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 atmospheric oxygen and moisture.
- it- is difficult to fill relatively long and narrow preformed tubes with particulate material and if initially a relatively short and wide tube is filled with the particulate material and is then drawn to a desired smaller diameter, the drawing constitutes an additional manufacturing step.
- 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.
- 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 reactive 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 0 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.
- the diameter of the tube is preferably 1 to 20 mm, especially 5 to. 15 mm, and its wall thickness 0.05 to 3 mm, especially 0.1 to 1 mm. 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 t ⁇ 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 comnunicates 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 art 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 . completely 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 Figures 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)
- Materials For Medical Uses (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
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 true EP0044183A1 (de) | 1982-01-20 |
EP0044183B1 EP0044183B1 (de) | 1985-03-20 |
Family
ID=10514653
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP81303066A Expired EP0044183B1 (de) | 1980-07-09 | 1981-07-06 | Metallurgische Behandlungsmittel |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0044183B1 (de) |
JP (1) | JPS6059972B2 (de) |
AT (1) | ATE12260T1 (de) |
AU (1) | AU542367B2 (de) |
DE (1) | DE3169368D1 (de) |
NO (1) | NO812327L (de) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6471742B2 (en) * | 2001-01-22 | 2002-10-29 | Oscar G. Dam | Method for producing an improved charging stock for use in metallurgical processes |
US7906747B2 (en) | 2004-06-10 | 2011-03-15 | Affival | Cored wire |
RU2487174C2 (ru) * | 2011-02-07 | 2013-07-10 | Закрытое акционерное общество "ФЕРРОСПЛАВ" | Способ обработки железоуглеродистого расплава и материал для его осуществления |
CN108176844A (zh) * | 2018-01-15 | 2018-06-19 | 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 |
CN112404372A (zh) * | 2020-11-20 | 2021-02-26 | 山东国铭球墨铸管科技有限公司 | 一种球墨铸铁的包内控速旋流球化方法 |
Families Citing this family (4)
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 |
DE3661841D1 (en) * | 1985-01-24 | 1989-02-23 | Vallourec | Process for treating liquid metals by a calcium-containing cored wire |
DE19827354A1 (de) * | 1998-06-19 | 1999-12-23 | Evertz Egon Kg Gmbh & Co | Verfahren zum Legieren von Stählen |
DE19916235C2 (de) * | 1999-03-01 | 2001-03-08 | Odermath Stahlwerkstechnik | Fülldraht zur Behandlung von Schmelzen mittels Drahtinjektion |
Citations (5)
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 |
DE2421743A1 (de) * | 1974-05-06 | 1975-11-20 | Ototani Tohei | Umkleidete calciumkoerper zum desoxidieren und entschwefeln von eisen- und stahlschmelzen u. dgl. |
US4134196A (en) * | 1975-07-25 | 1979-01-16 | Hitachi Cable Ltd. | Method of production of a wire-shaped composite addition material |
WO1979000536A1 (en) * | 1978-01-23 | 1979-08-09 | Caterpillar Tractor Co | Method of making a filled tubular article and article made thereby |
-
1981
- 1981-07-06 DE DE8181303066T patent/DE3169368D1/de not_active Expired
- 1981-07-06 EP EP81303066A patent/EP0044183B1/de not_active Expired
- 1981-07-06 AT AT81303066T patent/ATE12260T1/de not_active IP Right Cessation
- 1981-07-08 NO NO812327A patent/NO812327L/no unknown
- 1981-07-09 JP JP56107559A patent/JPS6059972B2/ja not_active Expired
- 1981-07-14 AU AU72832/81A patent/AU542367B2/en not_active Ceased
Patent Citations (5)
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 |
DE2421743A1 (de) * | 1974-05-06 | 1975-11-20 | Ototani Tohei | Umkleidete calciumkoerper zum desoxidieren und entschwefeln von eisen- und stahlschmelzen u. dgl. |
US4134196A (en) * | 1975-07-25 | 1979-01-16 | Hitachi Cable Ltd. | Method of production of a wire-shaped composite addition material |
WO1979000536A1 (en) * | 1978-01-23 | 1979-08-09 | Caterpillar Tractor Co | Method of making a filled tubular article and article made thereby |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6471742B2 (en) * | 2001-01-22 | 2002-10-29 | Oscar G. Dam | Method for producing an improved charging stock for use in metallurgical processes |
US7906747B2 (en) | 2004-06-10 | 2011-03-15 | Affival | Cored wire |
RU2487174C2 (ru) * | 2011-02-07 | 2013-07-10 | Закрытое акционерное общество "ФЕРРОСПЛАВ" | Способ обработки железоуглеродистого расплава и материал для его осуществления |
CN108176844A (zh) * | 2018-01-15 | 2018-06-19 | 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 |
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 |
CN112404372A (zh) * | 2020-11-20 | 2021-02-26 | 山东国铭球墨铸管科技有限公司 | 一种球墨铸铁的包内控速旋流球化方法 |
Also Published As
Publication number | Publication date |
---|---|
ATE12260T1 (de) | 1985-04-15 |
JPS6059972B2 (ja) | 1985-12-27 |
JPS5741334A (en) | 1982-03-08 |
NO812327L (no) | 1982-01-11 |
DE3169368D1 (en) | 1985-04-25 |
EP0044183B1 (de) | 1985-03-20 |
AU7283281A (en) | 1982-01-14 |
AU542367B2 (en) | 1985-02-21 |
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