EP0053197A1 - Deoxidation process of a metal melt - Google Patents

Deoxidation process of a metal melt Download PDF

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Publication number
EP0053197A1
EP0053197A1 EP80107489A EP80107489A EP0053197A1 EP 0053197 A1 EP0053197 A1 EP 0053197A1 EP 80107489 A EP80107489 A EP 80107489A EP 80107489 A EP80107489 A EP 80107489A EP 0053197 A1 EP0053197 A1 EP 0053197A1
Authority
EP
European Patent Office
Prior art keywords
additive
melt
protective element
microalloying
pouring
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.)
Withdrawn
Application number
EP80107489A
Other languages
German (de)
French (fr)
Inventor
Jürg Reist
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.)
Georg Fischer AG
Original Assignee
Georg Fischer AG
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 Georg Fischer AG filed Critical Georg Fischer AG
Priority to EP80107489A priority Critical patent/EP0053197A1/en
Priority to AU77587/81A priority patent/AU7758781A/en
Priority to JP56189367A priority patent/JPS57121854A/en
Publication of EP0053197A1 publication Critical patent/EP0053197A1/en
Priority to ZA817958A priority patent/ZA817958B/en
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/20—Measures not previously mentioned for influencing the grain structure or texture; Selection of compositions therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D1/00—Treatment of fused masses in the ladle or the supply runners before casting
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D7/00—Casting ingots, e.g. from ferrous metals
    • B22D7/12—Appurtenances, e.g. for sintering, for preventing splashing

Definitions

  • the invention relates to a method for deoxidizing, microalloying or inoculating metal melts according to the preamble of claim 1.
  • the deoxidizing elements such as Al, Si, Mn and the like are because of the good affinity for oxygen, they are the first to be oxidized and transferred to the slag, or they remain in the melt as inclusions.
  • the Al content 'in an iron melt drops from 0.063% to 0.003% within 20 hours. Lowering the Al activity in the melt can lead to the formation of oxides such as e.g. Lead Cr oxides during casting and adversely affect the casting quality.
  • Periodic deoxidation in the holding furnace does not lead to success due to the presence of slag.
  • the existing oxides can be dissolved or converted into a harmless form.
  • the method is carried out by means of a device as characterized in subclaims 5 to 8.
  • a splash guard or a mudguard are described, which serve to prevent the mold from being cast on the mold base before the long-term effects of the impact from a certain height and with considerable kinetic energy To protect the pouring jet or to prevent spraying.
  • These protective devices are made of a material that slowly dissolves and is fully integrated into the melt. This is an iron sheet or grid with a corresponding shape.
  • the additive which is a deoxidizing agent such as Al, Si, M, AlSi, Fe, Ti, FeSi, FeMn or the like, can be an alloy component for microalloying or a vaccine additive can be added at a time of the alloy , to which it can exert its full effect, without this effect having subsided by long waiting for the melt, as is sometimes necessary when a large amount of the melt is treated and then poured intermittently.
  • a deoxidizing agent such as Al, Si, M, AlSi, Fe, Ti, FeSi, FeMn or the like
  • the protective element has just as much of the additive as is necessary for the respective reaction, which also saves material, since, in comparison, when treating the melt in the pan, it is usually necessary to overtreat to ensure the effect of the treatment during the entire intermittent period To maintain the casting process.
  • any conceivable type of manufacture can be used for this purpose, when coating or coating an iron base body with the additive, immersing the base body in a melt of the additive, flame or plasma spraying or the like is conceivable.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)

Abstract

For deoxidising, micro-alloying or inoculating a metal melt during ingot casting, it is proposed to combine the appropriate additive with a known protective element which is arranged at the bottom of the ingot mould for protection against the pouring stream, in order thus to be able to fix, so as to be equal and optimal, the time of addition of the additive, whether it be a deoxidant, a micro-alloying constituent or an inoculating additive, for all casting processes and also to optimise the added amount.

Description

Die Erfindung betrifft ein Verfahren zum Desoxidieren, Mikrolegieren oder Impfen von Metallschmelzen nach dem Oberbegriff des Anspruchs 1.The invention relates to a method for deoxidizing, microalloying or inoculating metal melts according to the preamble of claim 1.

Beim Warmhalten und auch beim direkten Vergiessen der Legierungen mit Hilfe einer Giesspfanne, besonders bei Legierungen, welche zu Oxidbildung neigen, wie Legierungen mit erhöhtem Cr-Gehalt, ist es manchmal schwierig, die Oxidbildung während des Giessens zu verhindern.When keeping the alloy warm and also pouring it directly using a ladle, especially alloys that tend to form oxides, such as alloys with an increased Cr content, it is sometimes difficult to prevent oxide formation during casting.

Besonders während des Warmhaltens der Schmelze bei der Giesstemperatur werden die desoxidierend wirkenden Elemente wie Al, Si, Mn u.ä. wegen der guten Affinität zum Sauerstoff als erste oxidiert und in die Schlacke überführt, oder sie verbleiben in der Schmelze als Einschlüsse. Zum Beispiel sinkt der Al-Gehalt' in einer Eisenschmelze innerhalb von 20 Stunden von 0.063 % auf 0.003 %. Die Senkung der Al-Aktivität in der Schmelze kann zur Bildung von Oxyden wie z.B. Cr-Oxiden während des Vergiessens führen und die Gussqualität ungünstig beeinflussen.Especially when the melt is kept warm at the casting temperature, the deoxidizing elements such as Al, Si, Mn and the like are because of the good affinity for oxygen, they are the first to be oxidized and transferred to the slag, or they remain in the melt as inclusions. For example, the Al content 'in an iron melt drops from 0.063% to 0.003% within 20 hours. Lowering the Al activity in the melt can lead to the formation of oxides such as e.g. Lead Cr oxides during casting and adversely affect the casting quality.

Periodische Desoxidation im Warmhalteofen führt wegen der Schlackenanwesenheit nicht zum Erfolg.Periodic deoxidation in the holding furnace does not lead to success due to the presence of slag.

Dieser Nachteil wurde besonders beim direkten Vergiessen des chromlegierten Weissgusseisens in der Kokille beobachtet. Durch die Strömung im Kokillenhohlraum werden die Oxide zur Wand gedrückt und mit dem erstarrten Metall überdeckt. Dies ergibt Narben, welche dann die Oberflächengüte des Abgusses beeinträchtigen.This disadvantage was particularly observed when the chrome-alloy white cast iron was poured directly into the mold. Due to the flow in the mold cavity, the oxides are pressed against the wall and covered with the solidified metal. This results in scars, which then impair the surface quality of the cast.

Durch Zugabe einer kontrollierten Menge an Desoxidationsmittel in die Giessform können die bestehenden Oxide gelöst oder in eine unschädliche Form überführt werden.By adding a controlled amount of deoxidizing agent to the casting mold, the existing oxides can be dissolved or converted into a harmless form.

Die Zugabe der Mittel in Form von Pulver oder stückig hat jedoch wegen der Strömung in der Kokille und hoher Erstarrungsgeschwindigkeiten nicht immer zum Erfolg geführt.However, the addition of the agents in the form of powder or lumps has not always been successful because of the flow in the mold and high solidification rates.

Es ist Aufgabe der Erfindung, ein Verfahren anzugeben, bei dem durch dosierte Zugabe von Desoxidationsmitteln oder anderen Zusätzen eine gleichmässige Verteilung und Abscheidung in der Schmelze herbeizuführen, so dass die oben beschriebenen ungünstigen Ergebnisse verhindert werden können.It is an object of the invention to provide a method in which a uniform distribution and separation in the melt can be brought about by metered addition of deoxidizing agents or other additives, so that the unfavorable results described above can be prevented.

Erfindungsgemäss wird dies mit einem Verfahren der eingangs genannten Art gewährleistet, welches zusätzlich die im Kennzeichen des Anspruchs 1 angeführten Merkmale aufweist.According to the invention, this is ensured by a method of the type mentioned at the outset, which additionally has the features stated in the characterizing part of claim 1.

Die Durchführung des Verfahrens erfolgt mittels einer Einrichtung, wie sie in den Unteransprüchen 5 bis 8 gekennzeichnet wird.The method is carried out by means of a device as characterized in subclaims 5 to 8.

In der CH-PS 581 513 und in der US-PS 4 040 596 werden ein Spritzschutzgitter bzw. ein Schutzblech beschrieben, welche dazu dienen, die Kokille beim Giessen vor den Dauerwirkungen des aus einer bestimmten Höhe und mit erheblicher kinetischer Energie auf den Kokillenboden auftreffenden Giessstrahls zu schützen bzw. das Spritzen zu verhindern. Diese Schutzeinrichtungen sind aus einem Material, welches sich langsam auflöst und voll in die Schmelze integriert wird. Hierbei handelt es sich um ein Eisenblech oder -gitter mit ensprechender Formgebung.In CH-PS 581 513 and in US-PS 4 040 596 a splash guard or a mudguard are described, which serve to prevent the mold from being cast on the mold base before the long-term effects of the impact from a certain height and with considerable kinetic energy To protect the pouring jet or to prevent spraying. These protective devices are made of a material that slowly dissolves and is fully integrated into the melt. This is an iron sheet or grid with a corresponding shape.

Das Wesen der Erfindung liegt nun darin, diese Schutzeinrichtungen mit dem gewünschten Zusatzstoff zu umgeben, zu verbinden oder sie direkt aus ihm herzustellen.The essence of the invention is now to surround these protective devices with the desired additive, to connect them or to produce them directly from it.

Hierdurch wird gewährleistet, dass der Zusatzstoff, bei dem es sich um ein Desoxidationsmittel wie Al, Si, M, AlSi, Fe, Ti, FeSi, FeMn oder dergleichen, einen Legierungsbestandteil zum Mikrolegieren oder einen Impfzusatz handeln kann zu einem Zeitpunkt der Legierung zugesetzt wird, zu dem er die volle Wirkung ausüben kann, ohne dass diese Wirkung durch langes Warten der Schmelze, wie es teilweise notwendig ist, wenn eine grosse Menge der Schmelze behandelt und dann intermittierend vergossen wird, wieder abklingen kann.This ensures that the additive, which is a deoxidizing agent such as Al, Si, M, AlSi, Fe, Ti, FeSi, FeMn or the like, can be an alloy component for microalloying or a vaccine additive can be added at a time of the alloy , to which it can exert its full effect, without this effect having subsided by long waiting for the melt, as is sometimes necessary when a large amount of the melt is treated and then poured intermittently.

Das Schutzelement weist gerade soviel des Zusatzstoffes auf, wie für die jeweilige Reaktion nötig ist, dadurch kann auch Material gespart werden, da im Vergleich dazu beim Behandeln der Schmelze in der Pfanne meist ein Ueberbehandeln nötig ist, um die Wirkung der Behandlung während des gesamten intermittierenden Giessvorgangs aufrecht zu erhalten.The protective element has just as much of the additive as is necessary for the respective reaction, which also saves material, since, in comparison, when treating the melt in the pan, it is usually necessary to overtreat to ensure the effect of the treatment during the entire intermittent period To maintain the casting process.

Wenn das Schutzelement aus dem entsprechenden Zusatzstoff direkt hergestellt ist, so kann jede denkbare Herstellungsart dafür Verwendung finden, beim Beschichten oder Ueberziehen eines Eisengrundkörpers mit dem Zusatzstoff ist ein Eintauchen des Grundkörpers in eine Schmelze des Zusatzstoffes, Flamm-oder Plasmaspritzen oder ähnliches denkbar.If the protective element is produced directly from the corresponding additive, any conceivable type of manufacture can be used for this purpose, when coating or coating an iron base body with the additive, immersing the base body in a melt of the additive, flame or plasma spraying or the like is conceivable.

Eine ähnliche Wirkung ist auch in Sandformen denkbar, wobei der Eingiessschutz als socher entfällt, hingegen die gleichmässige Verteilung des Desoxydations- oder Mikrolegierungselementes bleibt.A similar effect is also conceivable in sand molds, the pouring protection being omitted as a socher, while the even distribution of the deoxidation or microalloying element remains.

Claims (9)

l. Verfahren zum Desoxidieren, zum Mikrolegieren oder zum Impfen von Metallschmelzen, wobei der Metallschmelze ein Zusatzstoff in fester Form zugegeben wird, dadurch gekennzeichnet, dass dieser Zusatzstoff im Eingiessbereich des Eingiesssystems eingebracht wird, so dass eine intensive Vermischung des Zusatzstoffes mit der Schmelze erfolgt.l. Process for deoxidizing, microalloying or inoculating metal melts, an additive in solid form being added to the metal melt, characterized in that this additive is introduced in the pouring area of the pouring system, so that the additive is mixed intensively with the melt. 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass der Zusatzstoff in integrierter Weise mit einem im Eingiessbereich angeordneten Schutzelement, auf das der Giessstrahl beim Eingiessen der Schmelze in die Form trifft verbunden ist, wobei bereits in der Schmelze gebildete Oxide durch die beim Eingiessen erfolgende intensive Vermischung wieder zerstört oder in eine für die Gussqualität unschädliche Form übergeführt werden und eine intensive Vermischung des Impfmittels bzw. der Mikrolegierung erfolgt.2. The method according to claim 1, characterized in that the additive is connected in an integrated manner with a protective element arranged in the pouring area, which the pouring jet strikes when the melt is poured into the mold, the oxides already formed in the melt being produced by the one taking place during the pouring intensive mixing is destroyed again or converted into a form that is harmless to the casting quality and intensive mixing of the inoculant or the microalloy takes place. 3. Verfahren nach Anspruch 1 und 2, dadurch gekennzeichnet, dass das Schutzelement aus einem Drahtgitter besteht, das in eine Schmelze eines Desoxidationsmittels, eines Legierungsbestandteils zum Mikrolegieren oder eines Zusatzstoffes zum Impfen getaucht wurde.3. The method according to claim 1 and 2, characterized in that the protective element consists of a wire mesh which has been immersed in a melt of a deoxidizing agent, an alloy component for microalloying or an additive for vaccination. 4. Verfahren nach Anspruch 1, 2 und 3, dadurch gekennzeichnet, dass als Zusatzstoff Al, Si, Mn, AlSi, FeTi, FeSi, CerMM, Zr, V, oder FeMn verwendet wird.4. The method according to claim 1, 2 and 3, characterized in that as additive Al, Si, Mn, AlSi, FeTi, FeSi, CerMM, Zr, V, or FeMn is used. 5. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass das Schutzelement ganz oder im wesentlichen aus Al, Si,Mn, AlSi, FeTi, FeSi, CerMM, Zr, V oder FeMn besteht.5. The method according to any one of claims 1 to 4, characterized in that the protective element consists entirely or essentially of Al, Si, Mn, AlSi, FeTi, FeSi, CerMM, Zr, V or FeMn. 6. Schutzelement zur Durchführung des Verfahrens nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass es eine für die jeweilige Menge an Schmelze für eine Giessform notwendige Menge eines Desoxidationsmittels, eines Legierungsbestandteils zum Mikrolegieren oder einen Zusatzstoff zum Impfen enthält.6. Protective element for carrying out the method according to any one of claims 1 to 5, characterized in that it contains an amount of a deoxidizing agent, an alloy component for microalloying or an additive for inoculation for the respective amount of melt for a casting mold. 7. Schutzelement nach Anspruch 6, dadurch gekennzeichnet, dass es aus einem Eisengitter besteht, welches mit einem Desoxidationsmittel, einem Legierungsbestandteil zum Mikrolegieren oder einem Zusatzstoff zum Impfen beschichtet ist.7. Protection element according to claim 6, characterized in that it consists of an iron grid which is coated with a deoxidizing agent, an alloy component for microalloying or an additive for vaccination. 8. Schutzelement nach Anspruch 6, dadurch gekennzeichnet, dass es aus einem, aus einem Desoxidationsmittel, einem Legierungsbestandteil zum Mikrolegieren oder einem Zusatzstoff zum Impfen gebildeten Gitter besteht.8. Protective element according to claim 6, characterized in that it consists of a grid formed from a deoxidizing agent, an alloy component for microalloying or an additive for seeding. 9. Schutzelement nach Anspruch 6, dadurch gekennzeichnet, dass die Beschichtung durch Eintauchen, Flammspritzen oder Plasmaspritzen hergestellt ist.9. Protective element according to claim 6, characterized in that the coating is produced by immersion, flame spraying or plasma spraying.
EP80107489A 1980-11-29 1980-11-29 Deoxidation process of a metal melt Withdrawn EP0053197A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP80107489A EP0053197A1 (en) 1980-11-29 1980-11-29 Deoxidation process of a metal melt
AU77587/81A AU7758781A (en) 1980-11-29 1981-11-18 Deoxidation, micro-alloying or inoculating a casting melt
JP56189367A JPS57121854A (en) 1980-11-29 1981-11-27 Casting method and protective member for mold used for said method
ZA817958A ZA817958B (en) 1980-11-29 1982-11-17 Method and apparatus for deoxidation,micro-alloying or inoculating a casting melt

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP80107489A EP0053197A1 (en) 1980-11-29 1980-11-29 Deoxidation process of a metal melt

Publications (1)

Publication Number Publication Date
EP0053197A1 true EP0053197A1 (en) 1982-06-09

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EP80107489A Withdrawn EP0053197A1 (en) 1980-11-29 1980-11-29 Deoxidation process of a metal melt

Country Status (3)

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EP (1) EP0053197A1 (en)
JP (1) JPS57121854A (en)
ZA (1) ZA817958B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012153333A1 (en) 2011-05-09 2012-11-15 Yissum Research Development Company Of The Hebrew University Of Jerusalem Ltd. Regeneration and repair of mesenchymal tissue using amelogenin
DE102014017925A1 (en) 2013-12-04 2015-07-02 Horst Diesing Apparatus and method for microcharging and / or microalloying molten metals

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE810061C (en) * 1948-10-26 1951-08-06 Henri Jean Dipl-Ing Daussan Device for improving the ingot quality in chill casting
DE1189239B (en) * 1961-05-25 1965-03-18 Henri Jean Daussan Method and device for cleaning iron alloys during casting
US3658115A (en) * 1970-11-30 1972-04-25 Gen Motors Corp Method of inoculating nodular cast iron
FR2278428A1 (en) * 1974-07-19 1976-02-13 Doittau Sa Produits Metallurg Splash absorber for top-poured steel ingot moulds - made of corrugated paper coated with aluminium
DE2608282A1 (en) * 1976-02-28 1977-09-08 Baur Eduard Dr Ing Adding inoculants and/or alloying agents to metal before casting - where agents are located in pouring funnel used to fill mould

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE810061C (en) * 1948-10-26 1951-08-06 Henri Jean Dipl-Ing Daussan Device for improving the ingot quality in chill casting
DE1189239B (en) * 1961-05-25 1965-03-18 Henri Jean Daussan Method and device for cleaning iron alloys during casting
US3658115A (en) * 1970-11-30 1972-04-25 Gen Motors Corp Method of inoculating nodular cast iron
FR2278428A1 (en) * 1974-07-19 1976-02-13 Doittau Sa Produits Metallurg Splash absorber for top-poured steel ingot moulds - made of corrugated paper coated with aluminium
DE2608282A1 (en) * 1976-02-28 1977-09-08 Baur Eduard Dr Ing Adding inoculants and/or alloying agents to metal before casting - where agents are located in pouring funnel used to fill mould

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012153333A1 (en) 2011-05-09 2012-11-15 Yissum Research Development Company Of The Hebrew University Of Jerusalem Ltd. Regeneration and repair of mesenchymal tissue using amelogenin
DE102014017925A1 (en) 2013-12-04 2015-07-02 Horst Diesing Apparatus and method for microcharging and / or microalloying molten metals
DE102014017925A8 (en) * 2013-12-04 2015-07-16 Horst Diesing Apparatus and method for microcharging and / or microalloying molten metals
DE102014017925B4 (en) * 2013-12-04 2017-02-09 Horst Diesing Apparatus and method for microcharging and / or microalloying molten metals

Also Published As

Publication number Publication date
JPS57121854A (en) 1982-07-29
ZA817958B (en) 1983-03-30

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