EP0406047B1 - Verfahren zum Wärmebehandeln von Metallen - Google Patents

Verfahren zum Wärmebehandeln von Metallen Download PDF

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Publication number
EP0406047B1
EP0406047B1 EP90401645A EP90401645A EP0406047B1 EP 0406047 B1 EP0406047 B1 EP 0406047B1 EP 90401645 A EP90401645 A EP 90401645A EP 90401645 A EP90401645 A EP 90401645A EP 0406047 B1 EP0406047 B1 EP 0406047B1
Authority
EP
European Patent Office
Prior art keywords
nitrogen
metals
heat treatment
atmosphere
treatment
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.)
Revoked
Application number
EP90401645A
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English (en)
French (fr)
Other versions
EP0406047A1 (de
Inventor
Yannick Rancon
Eric Duchateau
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.)
Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Original Assignee
Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Publication date
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=9383322&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0406047(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Air Liquide SA, LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude filed Critical Air Liquide SA
Publication of EP0406047A1 publication Critical patent/EP0406047A1/de
Application granted granted Critical
Publication of EP0406047B1 publication Critical patent/EP0406047B1/de
Anticipated expiration legal-status Critical
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/76—Adjusting the composition of the atmosphere
    • C21D1/763—Adjusting the composition of the atmosphere using a catalyst
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/76—Adjusting the composition of the atmosphere
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
    • C21D3/02—Extraction of non-metals
    • C21D3/04—Decarburising
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/02—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working in inert or controlled atmosphere or vacuum

Definitions

  • the invention relates to the heat treatment of metals in a continuous furnace by continuous passage of metal parts longitudinally in an elongated treatment zone under a controlled atmosphere having an upstream part at high temperature where said controlled atmosphere comprises nitrogen and reducing chemical species. , in particular hydrogen, possibly carbon monoxide and a downstream part of cooling under atmosphere formed essentially by admission of nitrogen.
  • the present invention relates to a method of heat treatment of metals in a continuous furnace which makes it possible to substantially reduce the cost of the treatment atmosphere while ensuring the requisite qualities of said atmosphere which must be devoid of oxygen both in the zone of treatment at high temperature than in the cooling zone and this method according to the invention is characterized in that, in the upstream part at high temperature, the nitrogen constituting the treatment atmosphere is supplied by admission of nitrogen to residual oxygen content not exceeding 5%, and preferably greater than 0.5%, produced by air separation according to permeation or adsorption techniques, in that the reducing species in said treatment atmosphere are at all moment present in contents at least sufficient to eliminate the oxygen thus admitted with the nitrogen, while the nitrogen admitted in the downstream part of cooling t, with a flow rate lower than the nitrogen flow rate admitted to the upstream portion at high temperature, is of the type developed prior to admission with practically zero oxygen content.
  • nitrogen is used industrially pure, that is to say nitrogen with practically zero oxygen content, which however only represents a flow rate of between 2% and 30%, preferably between 2 and 25%, of the total gas flow admitted in the treatment area.
  • the nitrogen admitted downstream from the cooling zone is produced according to the technique of air separation by cryogenic distillation.
  • the nitrogen admitted downstream from the cooling zone is produced according to the technique of air separation by permeation or adsorption producing crude nitrogen with residual oxygen content, which is eliminated. by catalytic reaction with a supply of hydrogen in an amount at least sufficient to ensure the elimination of residual oxygen.
  • the invention also relates to the application of the process to the annealing of metal parts.
  • Such annealing is carried out here in a continuous oven at a temperature of the order of 800 ° C.
  • water vapor can be added to the cooling zone to obtain, on the contrary, a bluing of the parts.
  • the annealing of copper tubes is carried out here in a continuous furnace at a temperature of the order of 650 ° C.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Furnace Details (AREA)
  • Separation By Low-Temperature Treatments (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Claims (9)

  1. Verfahren zur thermischen Behandlung von Metallen durch kontinuierliches Hindurchführen von Metallteilen durch eine längliche Behandlungszone mit einer kontrollierten Atmosphäre, mit einem stromaufseitigen Abschnitt hoher Temperatur, in welchem die kontrollierte Atmosphäre Stickstoff und reduzierende chemische Stoffe, insbesondere Wasserstoff, gegebenenfalls Kohlenmonoxid, aufweist, und einem stromabseitigen Kühlabschnitt mit einer Atmosphäre, welche im wesentlichen durch Einleiten von Stickstoff gebildet wird, dadurch gekennzeichnet, daß in dem stromaufseitigen Abschnitt hoher Temperatur der die Atmosphäre bildende Stickstoff durch Einleiten von auf dem Wege der Luftzerlegung mittels Permeations- oder Adsorptionstechnik gewonnenem Stickstoff mit einem Restgehalt an Sauerstoff von weniger als 5 % geliefert wird, wobei die reduzierenden Stoffe in jedem Augenblick mit Gehalten vorliegen, die zumindest ausreichen, um den dabei mit dem Stickstoff eingeleiteten Sauerstoffzu entfernen, und daß der in dem stromabseitigen Kühlabschnitt mit einem gegenüber dem Durchfluß des in dem stromaufseitigen Abschnitt hoher Temperatur eingeleiteten Stickstoffs geringeren Durchfluß eingelassene Stickstoff ein solcher ist, der vor dem Einleiten mit einem Sauerstoffgehalt von praktisch Null gewonnen wurde.
  2. Verfahren zur thermischen Behandlung von Metallen nach Anspruch 1, dadurch gekennzeichnet, daß der Restsauerstoffgehalt des Stickstoffs zur Bildung der Atmosphäre des stromaufseitigen Abschnitts hoher Temperatur größer als 0,5 % ist.
  3. Verfahren zur thermischen Behandlung von Metallen nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß der in dem stromabseitigen Kühlabschnitt eingeleitete Stickstoffmittels Luftzerlegung durch kryogene Destillation gewonnen wird.
  4. Verfahren zur thermischen Behandlung von Metallen nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß der in den stromabseitigen Kühlabschnitt eingeleitete Stickstoff mittels Luftzerlegung durch Permeation oder Adsorption gewonnen wird, welche zu Rohstickstoff mit einem Sauerstoffrestgehalt führt, der mittels katalytischer Reaktion durch Hinzugeben von Wasserstoff in einer Menge entfernt wird, die zumindest ausreicht, um die Entfernung des Restsauerstoffs zu sichern.
  5. Verfahren zur thermischen Behandlung von Metallen nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß der in den stromabseitigen Kühlabschnitt der Behandlungszone eingeleitete Stickstoffdurchfluß zwischen 2 % und 25 % des gesamten Gasdurchflusses ist, der in die Behandlungszone eingeleitet wird.
  6. Anwendung des Verfahrens zur thermischen Behandlung von Metallen nach einem der Ansprüche 1 bis 5 beim Glühen von Metallteilen.
  7. Anwendung des Verfahrens zur thermischen Behandlung von Metallen nach Anspruch 6 beim Glühen von Stahlteilen, wobei in den stromaufseitigen Abschnitt der Behandlungszone, der eine hohe Temperatur hat, Stickstoff mit einem Sauerstoffrestgehalt und Methanol eingeleitet wird, woraus durch Kracken Wasserstoff und Kohlenmonoxid erzeugt wird, wobei der gesamte Vorgang so abläuft, daß die Atmosphäre für die Glühbehandlung Verhältnisse der Gehalte H₂/H₂O und der Gehalte CO/CO₂ hat, welche die reduzierende Eigenschaft der Behandlungsatmosphäre sichern.
  8. Anwendung des Verfahrens zur thermischen Behandlung von Metallen nach Anspruch 6 beim Entkohlungsglühen magnetischer Teile, wobei in den stromaufseitigen Abschnitt der Behandlungszone, der eine hohe Temperatur hat, Stickstoff mit einem Sauerstoffrestgehalt eingeleitet wird, woraus durch Reaktion mit den reduzierenden Stoffen Wasserdampf und Kohlendioxid mit Gehalten geliefert wird, die ausreichen, um die Entkohlung zu sichern, wobei die Verhältnisse der Gehalte H₂/H₂O und der Gehalte CO/CO₂ ausreichend bleiben, um jegliche Oxidation des Metalls in dem stromaufseitigen Abschnitt hoher Temperatur zu verhindern.
  9. Anwendung des Verfahrens zur thermischen Behandlung von Metallen nach Anspruch 6 beim Glühen von Kupfer- oder Bronzeteilen bei einer Temperatur zwischen 350 °C und 700 °C, wobei Stickstoff mit einem Sauerstoff- und Wasserstoffrestgehalt in den Abschnitt hoher Temperatur der Behandlungszone eingeleitet wird.
EP90401645A 1989-06-30 1990-06-14 Verfahren zum Wärmebehandeln von Metallen Revoked EP0406047B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8908786A FR2649123B1 (fr) 1989-06-30 1989-06-30 Procede de traitement thermique de metaux
FR8908786 1989-06-30

Publications (2)

Publication Number Publication Date
EP0406047A1 EP0406047A1 (de) 1991-01-02
EP0406047B1 true EP0406047B1 (de) 1995-08-16

Family

ID=9383322

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90401645A Revoked EP0406047B1 (de) 1989-06-30 1990-06-14 Verfahren zum Wärmebehandeln von Metallen

Country Status (7)

Country Link
US (1) US5069728A (de)
EP (1) EP0406047B1 (de)
JP (1) JPH0347914A (de)
CA (1) CA2020077A1 (de)
DE (1) DE69021658T2 (de)
ES (1) ES2075177T3 (de)
FR (1) FR2649123B1 (de)

Families Citing this family (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4016183A1 (de) * 1990-05-19 1991-11-21 Linde Ag Verfahren zur verbesserten bereitstellung von behandlungsgas bei waermebehandlungen
KR940003784B1 (ko) * 1990-07-31 1994-05-03 가와사키 세이데츠 가부시키가이샤 침탄 · 침질대를 구비한 연속 어닐링로
FR2668166B1 (fr) * 1990-10-18 1994-05-20 Air Liquide Procede d'elaboration d'une atmosphere controlee pour traitement thermique de metaux.
US5221369A (en) * 1991-07-08 1993-06-22 Air Products And Chemicals, Inc. In-situ generation of heat treating atmospheres using non-cryogenically produced nitrogen
US5259893A (en) * 1991-07-08 1993-11-09 Air Products And Chemicals, Inc. In-situ generation of heat treating atmospheres using a mixture of non-cryogenically produced nitrogen and a hydrocarbon gas
US5342455A (en) * 1991-07-08 1994-08-30 Air Products And Chemicals, Inc. In-situ generation of heat treating atmospheres using a mixture of non-cryogenically produced nitrogen and a hydrocarbon gas
DE4212307C2 (de) * 1992-04-13 1994-07-28 Messer Griesheim Gmbh Verfahren zur Herstellung eines Schutz- oder Reaktionsgases für die Wärmebehandlung von Metallen
US5320818A (en) * 1992-12-22 1994-06-14 Air Products And Chemicals, Inc. Deoxygenation of non-cryogenically produced nitrogen with a hydrocarbon
US5284526A (en) * 1992-12-22 1994-02-08 Air Products And Chemicals, Inc. Integrated process for producing atmospheres suitable for heat treating from non-cryogenically generated nitrogen
US5417774A (en) * 1992-12-22 1995-05-23 Air Products And Chemicals, Inc. Heat treating atmospheres
US5298090A (en) * 1992-12-22 1994-03-29 Air Products And Chemicals, Inc. Atmospheres for heat treating non-ferrous metals and alloys
US5254180A (en) * 1992-12-22 1993-10-19 Air Products And Chemicals, Inc. Annealing of carbon steels in a pre-heated mixed ambients of nitrogen, oxygen, moisture and reducing gas
US5348592A (en) * 1993-02-01 1994-09-20 Air Products And Chemicals, Inc. Method of producing nitrogen-hydrogen atmospheres for metals processing
US5401339A (en) * 1994-02-10 1995-03-28 Air Products And Chemicals, Inc. Atmospheres for decarburize annealing steels
WO1995029270A1 (en) * 1994-04-25 1995-11-02 Sturm, Ruger & Company, Inc. Method of treating titanium parts
US5968457A (en) * 1994-06-06 1999-10-19 Praxair Technology, Inc. Apparatus for producing heat treatment atmospheres
US5441581A (en) * 1994-06-06 1995-08-15 Praxair Technology, Inc. Process and apparatus for producing heat treatment atmospheres
NZ314334A (en) * 1996-04-19 1997-09-22 Boc Group Inc Method of heat treating a metal with nitrogen rich gas preheated and then having oxygen-reactive gas added
IT1291205B1 (it) * 1997-03-18 1998-12-29 Rivoira S P A Procedimento per la generazione di un'atmosfera protettiva a basso punto di rugiada ed esente da ossigeno, per l'effettuazione di
US6168774B1 (en) 1997-08-07 2001-01-02 Praxair Technology, Inc. Compact deoxo system
US6458217B1 (en) 2000-02-29 2002-10-01 American Air Liquide, Inc. Superadiabatic combustion generation of reducing atmosphere for metal heat treatment
US6533996B2 (en) * 2001-02-02 2003-03-18 The Boc Group, Inc. Method and apparatus for metal processing
DE10347312B3 (de) * 2003-10-08 2005-04-14 Air Liquide Deutschland Gmbh Verfahren zur Wärmebehandlung von Eisenwerkstoffen

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DE2844167C2 (de) * 1978-10-10 1984-07-26 Fa. J. Aichelin, 7015 Korntal Verfahren zur Erzeugung einer Stickstoff-Schutzgasatmosphäre in einer Ofenkammer und Schutzgasindustrieofen zur Durchführung dieses Verfahrens
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Also Published As

Publication number Publication date
FR2649123B1 (fr) 1991-09-13
EP0406047A1 (de) 1991-01-02
US5069728A (en) 1991-12-03
CA2020077A1 (fr) 1990-12-31
DE69021658D1 (de) 1995-09-21
FR2649123A1 (fr) 1991-01-04
DE69021658T2 (de) 1996-02-01
ES2075177T3 (es) 1995-10-01
JPH0347914A (ja) 1991-02-28

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