EP1160349A1 - Procédé et appareil de traitement thermique de pièces métalliques - Google Patents

Procédé et appareil de traitement thermique de pièces métalliques Download PDF

Info

Publication number
EP1160349A1
EP1160349A1 EP00111129A EP00111129A EP1160349A1 EP 1160349 A1 EP1160349 A1 EP 1160349A1 EP 00111129 A EP00111129 A EP 00111129A EP 00111129 A EP00111129 A EP 00111129A EP 1160349 A1 EP1160349 A1 EP 1160349A1
Authority
EP
European Patent Office
Prior art keywords
phase
gas atmosphere
nitrogen
workpieces
during
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
EP00111129A
Other languages
German (de)
English (en)
Other versions
EP1160349B1 (fr
Inventor
Wolfgang Dr. Lerche
Bernd Dr. Edenhofer
Michael Dr. Lohrmann
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.)
Ipsen International GmbH
Original Assignee
Ipsen International GmbH
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 Ipsen International GmbH filed Critical Ipsen International GmbH
Priority to AT00111129T priority Critical patent/ATE274073T1/de
Priority to EP00111129A priority patent/EP1160349B1/fr
Priority to DE50007480T priority patent/DE50007480D1/de
Publication of EP1160349A1 publication Critical patent/EP1160349A1/fr
Application granted granted Critical
Publication of EP1160349B1 publication Critical patent/EP1160349B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/20—Carburising
    • C23C8/22—Carburising of ferrous surfaces
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/28—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases more than one element being applied in one step
    • C23C8/30—Carbo-nitriding
    • C23C8/32—Carbo-nitriding of ferrous surfaces

Definitions

  • the invention relates to a method for heat treatment of metallic Workpieces, especially for carburizing or carbonitriding Ferrous materials. It also relates to a device with which one can carry out such procedure.
  • thermochemical heat treatment To create defined workpiece properties, such as a high one Wear resistance or fatigue strength, metallic workpieces become one subjected to thermochemical heat treatment.
  • the result of Heat treatment is the enrichment of carburizing or carbonitriding Surface layer of the workpieces with carbon and / or nitrogen, due to the changed material composition of the workpieces after a subsequent hardening to give the required mechanical properties.
  • the treatment result is of particular influence general process parameters pressure, temperature and treatment time in primarily the composition of the enrichment of the boundary layer Carbon and / or nitrogen causing gas atmosphere. It can be about be required to add a reducing agent to the gas atmosphere in order to obtain a impermissibly high oxidation of the surface of the workpieces due to the Loading the workpieces in a heat treatment furnace due to the to avoid inevitable air entry noticeable oxygen.
  • the prior art also includes a number of procedures known to the composition of the gas atmosphere in terms of to adjust the desired treatment outcome.
  • the gas atmosphere is in Depending on the carburizing temperature in its carburizing effect on the adapt to the respective requirements.
  • This is a common practice So-called saturation compensation method, in which during a Enrichment phase the maximum possible amount of carbon in the Gas atmosphere is provided to saturate the surface layer with Reach carbon in a short time.
  • the exchange of substances with the gas atmosphere restricted or prevented by either using a gas atmosphere reduced carbon supply set or the gas atmosphere evacuated or is exchanged for an inert gas.
  • EP-A-0 080 124 describes a case hardening process known metallic workpieces, in which by pulsating addition carbon-containing gas components achieved a high carbon potential gradient becomes. The supply of the carbon-containing gas takes place in several cycles instead of and is interrupted as soon as saturation occurs in the boundary layer Carbon is reached.
  • GB-A-2 202 238 discloses a method for Carburizing workpieces, in which the enrichment phase and the Diffusion phase periodically until a desired carburization depth is reached alternate to the desired carbon content of the surface layer and the target carburization depth largely independent of each other and in to achieve as short a time as possible.
  • a disadvantage of all these processes is that they are not always satisfactory Treatment outcome. This is mainly due to the fact that during a diffusion phase following the enrichment phase or Temperature compensation phase no longer has any direct influence on the There is carbon content in the surface layer. This comes in particular Dimensions to be taken into account when there are small amounts of carbon dioxide or Water vapor are in the gas atmosphere, for example due to a Air entry at leaks of a heat treatment furnace are formed and which cause an increased degradation of the carbon in the surface layer.
  • those used to regulate carbon levels during the Process gases used in the enrichment phase oxygen-containing components, such as carbon monoxide, carbon dioxide or Water vapor due to the partial pressure of oxygen in the outside Edge area of the carburized edge layer an undesirable edge oxidation cause.
  • the invention is based, a method and a task To create device for heat treatment of metallic workpieces which to avoid carbide formation on the surface of the treating workpieces in a comparatively simple way an improved Treatment result.
  • Such a procedure adopts the knowledge that one can achieve improved treatment results of the workpieces if both during the enrichment phase and during the diffusion phase the carbon content of the boundary layer by varying that of the gas atmosphere supplied volume flows of nitrogen and hydrocarbon in one predetermined interval between a lower limit and an upper limit is set.
  • Nitrogen is reduced and the proportion of hydrocarbon is increased high carbon supply in the gas atmosphere, which in a relatively short Time the carbon content of the boundary layer up to the specified upper limit enriches.
  • the temperature to which heating takes place in the heating phase, the length of time for which the workpieces are kept at this temperature during the compensation phase, the temperatures which are set in the enrichment phase and the diffusion phase, and the amounts of nitrogen supplied in the respective process stages and carbon depend primarily on the material of the workpieces to be treated, the specific composition of the gas atmosphere required to achieve the desired carbon content of the surface layer and the desired treatment success, such as the desired carburization depth. Since the process parameters of the material properties depend on the workpieces to be treated, can be obtained from publicly available databases, such as the Calphad (Cal culation of pha se d iagrams), Sweden, necessary for a particular steel composition parameter values with respect to the desired carbon content in the Remove surface layer.
  • the amounts of nitrogen and Hydrocarbon in the gas atmosphere during the enrichment phase and / or the diffusion phase advantageously varies such that the Upper limit of the carbon content of the surface layer slightly below the due to carbide formation occurring at the prevailing temperature marked saturation of austenite.
  • the upper limit of Carbon content of the surface layer can be so during the diffusion phase be chosen to meet the requirements of one of the following Cooling phase takes place corresponding hardening process.
  • a particularly advantageous procedure is also given if the workpieces during the heating phase to one for carburizing or Carbonitrieren favorable temperature between 750 ° C and 1050 ° C to be heated.
  • a carbon content of the surface layer is also of particular advantage during the heating phase in the range between 0.2 wt .-% and 0.5 wt .-%. Possibly existing oxide or passive layers on the workpieces are eliminated in this way or at least converted so that a uniform diffusion of carbon into the material is favored.
  • a reduced temperature during the enrichment phase during the diffusion phase be useful.
  • a particularly advantageous procedure is also given when unsaturated hydrocarbons of the type C n H 2n , preferably alkenes such as ethylene (C 2 H 4 ) and propylene (C 3 H 6 ), saturated hydrocarbons of the type C n H 2n + 2 , preferably alkanes such as ethane (C 2 H 6 ) and propane (C 3 H 8 ), or alkynes such as acetylene (C 2 H 2 ) are added to the gas atmosphere.
  • alkynes in particular which are distinguished by a low proportion of hydrogen, offer the advantage that no further fission products are produced and the proportion of hydrogen in the gas atmosphere accordingly remains low.
  • a reducing agent preferably hydrogen
  • a reducing agent is advantageously added to the gas atmosphere in the case of oxygen present in the gas atmosphere, which results, for example, from an air entry at leaks in a heat treatment furnace constant or variable amount added.
  • the time and the amount of reducing agent added depend on the circumstances in each case.
  • the supply of the amounts of nitrogen and hydrocarbon into the gas atmosphere is regulated or controlled in a database-dependent manner as a function of a characteristic value representing the carbon content in the surface layer, preferably the carbonation index K c .
  • the database-related control is advantageous if a characteristic value representing the carbon content in the surface layer is not available, for example due to measurement difficulties.
  • the regulation of the supply as a function of a characteristic value representing the carbon content in the surface layer enables the desired carbon content of the surface layer to be set precisely, without the particular size of the surface of the workpieces to be treated being important.
  • the workpieces are expediently removed during the cooling phase a reducing or neutral gas atmosphere or in a liquid Quench medium cooled to room temperature.
  • a device for heat treating metallic workpieces which has a heating chamber in which the workpieces can be heated and exposed to a gas atmosphere containing nitrogen and a hydrocarbon, and is characterized in that means are provided with which the supply the amounts of nitrogen and hydrocarbon in the gas atmosphere as a function of a characteristic value representative of the carbon content in the surface layer, preferably the carbonation index K c , can be regulated or controlled in a database-related manner.
  • the method according to the invention can be carried out in a reliable manner.
  • the Heating chamber is hermetically sealed to prevent air from entering and thus avoid oxygen in the gas atmosphere.
  • the heating chamber be filled with an inert gas, preferably nitrogen, is flushable, so that regardless of the volume of the heating chamber, the content of Oxygen in the atmosphere of the heating chamber after introduction of the treating workpieces in a comparatively short time to ⁇ 1% by volume reducible and undesirable oxidation of the workpieces to be treated this is avoidable.
  • the time t is on the abscissa and the temperature ⁇ on the ordinate, the carbon content w c resulting in the surface layer of workpieces to be treated, and the volume flows of hydrogen V ⁇ H2 supplied to a gas atmosphere for this purpose , Nitrogen V ⁇ N 2 , ammonia V ⁇ NH3 and the hydrocarbon acetylene V ⁇ C 2 H 2 removed.
  • the heat treatment method shown in Fig. 1 is primarily used for carburizing metallic workpieces, which can consist of different steels. The entire process can be divided into five phases. In a first phase, the heating phase A, the workpieces are heated to a carburizing temperature ⁇ of, for example, 930 ° C.
  • the heat treatment furnace used for this purpose an atmosphere furnace, was flushed with nitrogen in a short time after the workpieces had been introduced, and was then flooded with a gas atmosphere containing nitrogen and acetylene.
  • the size of the volume flows of nitrogen V ⁇ N 2 and acetylene V ⁇ C 2 H 2 supplied to the gas atmosphere is such that an edge layer with a carbon content w c of approx. 0.35% by weight is established on the workpieces.
  • the supply of the amounts of nitrogen V ⁇ N 2 and acetylene V ⁇ C 2 H 2 into the gas atmosphere is regulated depending on a characteristic value representing the carbon content w c in the surface layer, which is determined by a measuring device.
  • a constant volume flow of hydrogen V ⁇ H 2 of approximately 0.3 m 3 / h is also supplied to the gas atmosphere during the heating phase A in order to bring the gas atmosphere into a sufficiently reducing state.
  • a compensation phase B following the heating-up phase A the workpieces are kept at the temperature ⁇ reached at the end of the heating-up phase A of approx. 930 ° C. for approx. 20 min.
  • the quantities of nitrogen V ⁇ N 2 and acetylene V ⁇ C 2 H 2 fed into the gas atmosphere are further regulated in such a way that a carbon content w c in the surface layer of the workpieces of approx. 0.35% by weight results.
  • the volume flow of hydrogen V ⁇ H 2 is reduced to a value of less than 0.2 m 3 / h.
  • the volume flows of nitrogen V ⁇ N 2 and acetylene V ⁇ C 2 H 2 supplied to the gas atmosphere are varied such that a carbon content w c of the boundary layer varies in an interval between a lower limit G u of approx. 0.7% by weight and an upper limit G o of approx. 1.2% by weight.
  • the upper limit G o of approx. 1.2 wt At the temperature ⁇ of approx. 930 ° C which continues to exist in the enrichment phase C, the upper limit G o of approx. 1.2 wt.
  • the volume flow of nitrogen V ⁇ N 2 is reduced in a first section and the volume flow of acetylene V ⁇ C 2 H 2 is increased.
  • the volume flow of nitrogen V ⁇ N 2 is increased again in a second section to reach the lower limit G u , whereas the volume flow of acetylene V ⁇ C 2 H 2 is reduced.
  • the first and second sections are repeated alternately within the enrichment phase C, whereby an adaptation of the enrichment of the surface layer with carbon is achieved in accordance with the absorption capacity of the workpieces, which depends on the respective material.
  • the duration and therefore the respective size of the volume flows of nitrogen V ⁇ N 2 and acetylene V ⁇ C 2 H 2 during the first and second sections is uneven, such as the differently steep flanks of the curve of the carbon content w c in Fig. 1 can be seen.
  • the system and process-adapted volume flow of hydrogen V ⁇ H 2 is increased to approx. 0.2 m 3 / h during the enrichment phase C.
  • the enrichment phase C is followed by a diffusion phase D in which the temperature ⁇ is reduced to approximately 880 ° C. With regard to a subsequent hardening process, the upper limit G o is reduced to approximately 0.8% by weight.
  • the thermodynamic equilibrium between the gas atmosphere and the surface layer of the workpieces to be treated is adjusted by varying the volume flows of nitrogen V ⁇ N2 and acetylene V ⁇ C 2 H 2 supplied to the gas atmosphere in such a way that first and second sections the carbon content w c of the boundary layer lies in the interval between the lower limit G u of approximately 0.7% by weight and the upper limit G o of approximately 0.8% by weight.
  • the system and process-adapted volume flow of hydrogen V lagen H 2 is reduced again during the diffusion phase D to a value below 0.2 m 3 / h.
  • the workpieces are cooled to room temperature during a cooling phase E following the diffusion phase D.
  • the process described above is characterized by the volumetric flow control of the amounts of nitrogen V ⁇ N 2 and acetylene V 2 C 2 H 2 supplied to the gas atmosphere in the individual process stages, which results in an improved treatment result compared to conventional carburizing processes.
  • the main reason for this is that the carbon supply in the gas atmosphere can be adapted in this way according to the material and the surface of the workpieces to be treated and thus the absorption capacity of the surface layer.
  • the possibility to provide alternating first and second sections of different carbon contents w c during the enrichment phase C and the diffusion phase D also contributes to this result to a particular degree.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • Heat Treatment Of Articles (AREA)
  • Furnace Details (AREA)
EP00111129A 2000-05-24 2000-05-24 Procédé et appareil de traitement thermique de pièces métalliques Expired - Lifetime EP1160349B1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
AT00111129T ATE274073T1 (de) 2000-05-24 2000-05-24 Verfahren und vorrichtung zur wärmebehandlung metallischer werkstücke
EP00111129A EP1160349B1 (fr) 2000-05-24 2000-05-24 Procédé et appareil de traitement thermique de pièces métalliques
DE50007480T DE50007480D1 (de) 2000-05-24 2000-05-24 Verfahren und Vorrichtung zur Wärmebehandlung metallischer Werkstücke

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP00111129A EP1160349B1 (fr) 2000-05-24 2000-05-24 Procédé et appareil de traitement thermique de pièces métalliques

Publications (2)

Publication Number Publication Date
EP1160349A1 true EP1160349A1 (fr) 2001-12-05
EP1160349B1 EP1160349B1 (fr) 2004-08-18

Family

ID=8168822

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00111129A Expired - Lifetime EP1160349B1 (fr) 2000-05-24 2000-05-24 Procédé et appareil de traitement thermique de pièces métalliques

Country Status (3)

Country Link
EP (1) EP1160349B1 (fr)
AT (1) ATE274073T1 (fr)
DE (1) DE50007480D1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003097893A1 (fr) * 2002-05-15 2003-11-27 Linde Aktiengesellschaft Procede et dispositif de traitement thermique de pieces metalliques
WO2004040033A1 (fr) * 2002-10-31 2004-05-13 Seco/Warwick Sp. Z O.O. Procede de cementation par sous-pression de pieces d'acier
WO2005038076A1 (fr) * 2003-10-14 2005-04-28 Etudes Et Constructions Mecaniques Procede et four de cementation basse pression
FR2884523A1 (fr) * 2005-04-19 2006-10-20 Const Mecaniques Sa Et Procede et four de carbonitruration a basse pression
WO2008083031A1 (fr) * 2006-12-26 2008-07-10 Praxair Technology, Inc. Procédé d'optimisation d'un processus de traitement thermique sans oxygène
WO2012048669A1 (fr) 2010-10-11 2012-04-19 Ipsen International Gmbh Procédé et dispositif de carburation et carbonitruration de matériaux métalliques
WO2016046265A1 (fr) * 2014-09-24 2016-03-31 Robert Bosch Gmbh Procédé de traitement d'un matériau ferreux et matériau ferreux traité
US10280500B2 (en) 2010-04-23 2019-05-07 Robert Bosch Gmbh Process for carbonitriding metallic components

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0080124A2 (fr) * 1981-11-20 1983-06-01 Linde Aktiengesellschaft Procédé de cémentation de pièces métalliques
US5139584A (en) * 1989-07-13 1992-08-18 Solo Fours Industriels Sa Carburization process
DE19704871C1 (de) * 1997-02-10 1998-10-15 Will Haertetechnik Gmbh Verfahren zum Härten von Hohlwellen und nach diesem Verfahren hergestellte Hohlwellen
FR2777911A1 (fr) * 1998-04-28 1999-10-29 Aubert & Duval Sa Procede de carbonitruration a basse pression de pieces en alliage metallique

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0080124A2 (fr) * 1981-11-20 1983-06-01 Linde Aktiengesellschaft Procédé de cémentation de pièces métalliques
US5139584A (en) * 1989-07-13 1992-08-18 Solo Fours Industriels Sa Carburization process
DE19704871C1 (de) * 1997-02-10 1998-10-15 Will Haertetechnik Gmbh Verfahren zum Härten von Hohlwellen und nach diesem Verfahren hergestellte Hohlwellen
FR2777911A1 (fr) * 1998-04-28 1999-10-29 Aubert & Duval Sa Procede de carbonitruration a basse pression de pieces en alliage metallique

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003097893A1 (fr) * 2002-05-15 2003-11-27 Linde Aktiengesellschaft Procede et dispositif de traitement thermique de pieces metalliques
WO2004040033A1 (fr) * 2002-10-31 2004-05-13 Seco/Warwick Sp. Z O.O. Procede de cementation par sous-pression de pieces d'acier
WO2005038076A1 (fr) * 2003-10-14 2005-04-28 Etudes Et Constructions Mecaniques Procede et four de cementation basse pression
FR2884523A1 (fr) * 2005-04-19 2006-10-20 Const Mecaniques Sa Et Procede et four de carbonitruration a basse pression
WO2006111683A1 (fr) 2005-04-19 2006-10-26 Etudes Et Constructions Mecaniques Procede et four de carbonitruration a basse pression
US8303731B2 (en) 2005-04-19 2012-11-06 Ecm Technologies Low pressure carbonitriding method and device
WO2008083031A1 (fr) * 2006-12-26 2008-07-10 Praxair Technology, Inc. Procédé d'optimisation d'un processus de traitement thermique sans oxygène
US10280500B2 (en) 2010-04-23 2019-05-07 Robert Bosch Gmbh Process for carbonitriding metallic components
WO2012048669A1 (fr) 2010-10-11 2012-04-19 Ipsen International Gmbh Procédé et dispositif de carburation et carbonitruration de matériaux métalliques
WO2016046265A1 (fr) * 2014-09-24 2016-03-31 Robert Bosch Gmbh Procédé de traitement d'un matériau ferreux et matériau ferreux traité

Also Published As

Publication number Publication date
DE50007480D1 (de) 2004-09-23
EP1160349B1 (fr) 2004-08-18
ATE274073T1 (de) 2004-09-15

Similar Documents

Publication Publication Date Title
EP0049530B1 (fr) Procédé et dispositif pour carburer des pièces en acier
DE3486037T2 (de) Korrosionsgeschuetzte werkstuecke aus stahl und verfahren zu ihrer herstellung.
DE3419638C2 (de) Verfahren zur oxidativen Erzeugung von Schutzschichten auf einer Legierung
DE2450879A1 (de) Verfahren zur waermebehandlung von eisenmetallen
DE69032144T2 (de) Verfahren und Vorrichtung zur thermischen oder thermochemischen Behandlung von Stahl
DE2657644A1 (de) Gasmischung zum einfuehren in einen eisenmetallbehandlungsofen
DE2417179A1 (de) Verfahren zur aufkohlung hochlegierter staehle
DE2934930C2 (fr)
EP1160349B1 (fr) Procédé et appareil de traitement thermique de pièces métalliques
DE2754801A1 (de) Verfahren und vorrichtung zur erzeugung eines - insbesondere blattartigen - materials aus nicht oxydierbarem stahl
EP0662525B1 (fr) Procédé pour empêcher l'oxydation superficielle pendant la carburation des aciers
EP1019561B1 (fr) Procede et dispositif d'oxydation et de traitement thermique de groupes de pieces
DE69902169T2 (de) Verfahren zum niederdrück-nitrocarburieren metallischer werkstücke
DE3019830C2 (de) Verfahren zum Aufkohlen und Erwärmen von Werkstücken aus Stahl in geregelter Ofenatmospähre
WO2012048669A1 (fr) Procédé et dispositif de carburation et carbonitruration de matériaux métalliques
EP1122330B1 (fr) Procédé et utilisation d' un dispositif pour la carbonitruration de pièces métalliques
DE69608652T2 (de) Verfahren zum Aufkohlen von Metallen
EP1122331A1 (fr) Procédé pour la nitruration et/ou carbonitruration d' acier fortement allié
DE3139622C2 (de) Verfahren zur Gasaufkohlung von Stahl und Vorrichtung zu seiner Durchführung
DE19523956A1 (de) Verfahren zur Karburierungs- oder Karbonitrierungsbehandlung von Stählen
DE632935C (de) Verfahren und Einrichtung zur Oberflaechenkohlung von Eisen und Stahl
DE2109997B2 (de) Verfahren zum Oberflächeniegieren, insbesondere Inchromieren von Eisenwerkstoffen
DE60217344T2 (de) Verfahren zum abschrecken von stahl mittels druckluft
DE3120509C2 (de) Verfahren zum Gasnitrieren von Werkstücken aus Stahl
DE3017937C2 (de) Diffusionssinterverfahren in Stickstoff-Atmosphäre

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20001123

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

Kind code of ref document: A1

Designated state(s): AT CH DE ES FR GB IT LI

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17Q First examination report despatched

Effective date: 20020625

AKX Designation fees paid

Free format text: AT CH DE ES FR GB IT LI

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT CH DE ES FR GB IT LI

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20040818

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

Ref country code: CH

Ref legal event code: NV

Representative=s name: E. BLUM & CO. PATENTANWAELTE

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: GERMAN

REF Corresponds to:

Ref document number: 50007480

Country of ref document: DE

Date of ref document: 20040923

Kind code of ref document: P

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20041129

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20041203

REG Reference to a national code

Ref country code: IE

Ref legal event code: FD4D

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20050519

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 20060515

Year of fee payment: 7

Ref country code: CH

Payment date: 20060515

Year of fee payment: 7

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20060519

Year of fee payment: 7

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20060522

Year of fee payment: 7

REG Reference to a national code

Ref country code: CH

Ref legal event code: PFA

Owner name: IPSEN INTERNATIONAL GMBH

Free format text: IPSEN INTERNATIONAL GMBH#FLUTSTRASSE 78#47533 KLEVE (DE) -TRANSFER TO- IPSEN INTERNATIONAL GMBH#FLUTSTRASSE 78#47533 KLEVE (DE)

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20070524

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070531

Ref country code: AT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070524

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070531

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20080131

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070524

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20070531

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20140521

Year of fee payment: 15

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 50007480

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20151201