EP0406047A1 - Verfahren zum Wärmebehandeln von Metallen - Google Patents

Verfahren zum Wärmebehandeln von Metallen Download PDF

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Publication number
EP0406047A1
EP0406047A1 EP90401645A EP90401645A EP0406047A1 EP 0406047 A1 EP0406047 A1 EP 0406047A1 EP 90401645 A EP90401645 A EP 90401645A EP 90401645 A EP90401645 A EP 90401645A EP 0406047 A1 EP0406047 A1 EP 0406047A1
Authority
EP
European Patent Office
Prior art keywords
nitrogen
atmosphere
admitted
high temperature
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.)
Granted
Application number
EP90401645A
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English (en)
French (fr)
Other versions
EP0406047B1 (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
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
Family has litigation
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(A1) "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
Revoked legal-status Critical Current

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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.
  • This type of controlled atmosphere which is mainly used for the annealing of metal parts, has so far been produced as follows: - Either an exothermic generator is used ensuring the incomplete combustion of a hydrocarbon and air and delivering combustion gases which, after possible purification, contain hydrogen and carbon monoxide at contents which depend on the air ratio / hydrocarbon admitted into the generator.
  • such an exothermic atmosphere may contain 5 to 10% of carbon monoxide and 6 to 12% of hydrogen;
  • - Either a synthetic atmosphere is produced from pure industrial gases such as nitrogen and hydrogen. Nitrogen is produced by cryogenic distillation of air and contains very few impurities; for example, the total of water vapor and oxygen impurities is generally less than 10 vpm.
  • To this very pure nitrogen is added hydrogen, or a hydrocarbon, or hydrogen and a hydrocarbon, or methanol so as to produce a reducing atmosphere and, where appropriate, non-decarburizing to treat the metal parts.
  • 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%, typically produced by air separation according to permeation or adsorption techniques, in that the reducing species in said treatment atmosphere are at at all times present in contents at least sufficient to eliminate the oxygen thus admitted with nitrogen, while the nitrogen admitted partly downstream of re cooling is of the type developed before 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% of the total gas flow admitted into the treatment zone.
  • the admission of a low flow of deoxygenated nitrogen into the cold zone of the oven makes it possible to prevent the return of air and the use of less pure nitrogen in the hot zone makes it possible to reduce the operating costs without reducing the performances.
  • the nitrogen admitted in the downstream part of 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 H2 / H2O and CO / CO2 ratios are such that the treatment atmosphere is not oxidizing with respect to the metal. - we admit, at the downstream end of the cooling zone, in order to prevent any entry of air, 12 m3 / h (10% of the total flow) consisting of nitrogen produced by cryogenic distillation with an oxygen content of less than 10 vpm.
  • Such annealing is carried out here in a continuous oven at a temperature of the order of 800 ° C.
  • a total flow rate in the furnace of 100 m3 / h is allowed, which breaks down as follows: - 85 m3 / h (85% of the total flow) of a mixture consisting of 68 m3 / h of nitrogen with a residual oxygen content of 3% and 10 liters / hour of methanol is allowed in the hot zone which, by cracking in the furnace, produce approximately 11.3 m3 / h of hydrogen and 5.7 m3 / h of carbon monoxide. Residual oxygen immediately combines with reducing species to form water vapor and carbon dioxide which are the decarburizing agents of magnetic sheets.
  • 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.
  • a total flow rate of 180 m3 / h is allowed in the oven, which breaks down as follows: - 170 m3 / h (95% of the total flow) of a mixture consisting of 165 m3 / h of nitrogen with a residual oxygen content of 0.5% and 5 m3 / h of hydrogen.
  • a mixture consisting of 165 m3 / h of nitrogen with a residual oxygen content of 0.5% and 5 m3 / h of hydrogen By reaction with oxygen from oven, approximately 1.7 m3 / h of water vapor is formed, while approximately 3.3 m3 / h of hydrogen remains. In this way, oxygen is eliminated almost instantaneously so as not to oxidize the copper.
  • the presence of water vapor has no harmful effect taking into account the hydrogen content.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Thermal Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Furnace Details (AREA)
  • Separation By Low-Temperature Treatments (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
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 true EP0406047A1 (de) 1991-01-02
EP0406047B1 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)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0541006A2 (de) * 1991-11-05 1993-05-12 Air Products And Chemicals, Inc. In-Situ Erzeugung von Wärmebehandlungsatmosphären unter Verwendung von eine Mischung von nicht-kryogenisch hergestellte Stickstoff mit gasförmige Kohlenwasserstoffe
WO1993021350A1 (de) * 1992-04-13 1993-10-28 Messer Griesheim Gmbh Verfahren zur herstellung eines schutz- oder reaktionsgases für die wärmebehandlung von metallen

Families Citing this family (21)

* 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.
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
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
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
US5417774A (en) * 1992-12-22 1995-05-23 Air Products And Chemicals, Inc. Heat treating atmospheres
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
US5320818A (en) * 1992-12-22 1994-06-14 Air Products And Chemicals, Inc. Deoxygenation of non-cryogenically produced nitrogen with a hydrocarbon
US5298090A (en) * 1992-12-22 1994-03-29 Air Products And Chemicals, Inc. Atmospheres for heat treating non-ferrous metals and alloys
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
CN1151192A (zh) * 1994-04-25 1997-06-04 施图尔姆鲁格有限公司 处理钛部件的方法
US5441581A (en) * 1994-06-06 1995-08-15 Praxair Technology, Inc. Process and apparatus for producing heat treatment atmospheres
US5968457A (en) * 1994-06-06 1999-10-19 Praxair Technology, Inc. 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

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB671421A (en) * 1949-08-12 1952-05-07 Edward Alfred Wheeley Improvements in and relating to production of nitrogen or nitrogen-hydrogen mixtures
US3950192A (en) * 1974-10-30 1976-04-13 Monsanto Company Continuous carburizing method
GB2018299A (en) * 1978-01-17 1979-10-17 Boc Ltd Heat treatment of metal
FR2438687A1 (fr) * 1978-10-10 1980-05-09 Aichelin Gmbh Procede et four industriel a atmosphere controlee destines au traitement thermique des pieces metalliques
EP0027649A1 (de) * 1979-10-23 1981-04-29 Air Products And Chemicals, Inc. Verfahren zum Glühen oder Kugelglühen von Eisenmetallen in einer Schutzatmosphäre

Family Cites Families (8)

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DE1063624B (de) * 1957-07-25 1959-08-20 Robert Von Linde Dipl Ing Industrieofen
US3492378A (en) * 1968-05-13 1970-01-27 Bethlehem Steel Corp Method of operation of a continuous strip heating furnace
US4049472A (en) * 1975-12-22 1977-09-20 Air Products And Chemicals, Inc. Atmosphere compositions and methods of using same for surface treating ferrous metals
US4183773A (en) * 1975-12-25 1980-01-15 Nippon Kakan Kabushiki Kaisha Continuous annealing process for strip coils
US4334938A (en) * 1980-08-22 1982-06-15 Air Products And Chemicals, Inc. Inhibited annealing of ferrous metals containing chromium
US4415379A (en) * 1981-09-15 1983-11-15 The Boc Group, Inc. Heat treatment processes
FR2524006B1 (fr) * 1982-03-23 1985-10-11 Air Liquide Procede de durcissement superficiel de pieces metalliques
JPS63310915A (ja) * 1987-06-10 1988-12-19 Daido Steel Co Ltd 連続式熱処理炉の操業方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB671421A (en) * 1949-08-12 1952-05-07 Edward Alfred Wheeley Improvements in and relating to production of nitrogen or nitrogen-hydrogen mixtures
US3950192A (en) * 1974-10-30 1976-04-13 Monsanto Company Continuous carburizing method
GB2018299A (en) * 1978-01-17 1979-10-17 Boc Ltd Heat treatment of metal
FR2438687A1 (fr) * 1978-10-10 1980-05-09 Aichelin Gmbh Procede et four industriel a atmosphere controlee destines au traitement thermique des pieces metalliques
EP0027649A1 (de) * 1979-10-23 1981-04-29 Air Products And Chemicals, Inc. Verfahren zum Glühen oder Kugelglühen von Eisenmetallen in einer Schutzatmosphäre

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
ADVANCED MATERIALS & PROCESSES, vol. 134, no. 3, septembre 1988, pages 100-107; W.C. QUANTZ: "Stealing nitrogen from the air" *
J. HEAT TREATING, vol. 2, no. 1, 1981, pages 35-42; M. KOSTELITZ et al.: "Heat treating processes with nitrogen and methanol-based atmospheres" *
METAL SCIENCE & HEAT TREATMENT, vol. 30, nos. 5-6, mai-juin 1988, pages 408-414; N.A. TITOV: "Carbon potential and composition of a neutral controlled atmosphere produced from methane and a nitrogen-oxygen mixture" *
PATENT ABSTRACTS OF JAPAN, vol. 13, no. 156 (C-585)[3504], 14 avril 1989; & JP-A-63 310 915 (DAIDO STEEL) 19-12-1988 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0541006A2 (de) * 1991-11-05 1993-05-12 Air Products And Chemicals, Inc. In-Situ Erzeugung von Wärmebehandlungsatmosphären unter Verwendung von eine Mischung von nicht-kryogenisch hergestellte Stickstoff mit gasförmige Kohlenwasserstoffe
EP0541006A3 (en) * 1991-11-05 1993-08-04 Air Products And Chemicals, Inc. In-situ generation of heat treating atmospheres using a mixture of non-cryogenically produced nitrogen and a hydrocarbon gas
WO1993021350A1 (de) * 1992-04-13 1993-10-28 Messer Griesheim Gmbh Verfahren zur herstellung eines schutz- oder reaktionsgases für die wärmebehandlung von metallen

Also Published As

Publication number Publication date
FR2649123B1 (fr) 1991-09-13
EP0406047B1 (de) 1995-08-16
CA2020077A1 (fr) 1990-12-31
US5069728A (en) 1991-12-03
ES2075177T3 (es) 1995-10-01
FR2649123A1 (fr) 1991-01-04
JPH0347914A (ja) 1991-02-28
DE69021658T2 (de) 1996-02-01
DE69021658D1 (de) 1995-09-21

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