EP1101826A1 - Abschreckverfahren nach Niederdruck-Aufkohlung - Google Patents

Abschreckverfahren nach Niederdruck-Aufkohlung Download PDF

Info

Publication number
EP1101826A1
EP1101826A1 EP00410142A EP00410142A EP1101826A1 EP 1101826 A1 EP1101826 A1 EP 1101826A1 EP 00410142 A EP00410142 A EP 00410142A EP 00410142 A EP00410142 A EP 00410142A EP 1101826 A1 EP1101826 A1 EP 1101826A1
Authority
EP
European Patent Office
Prior art keywords
quenching
treatment
air
low pressure
cell
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Withdrawn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
EP00410142A
Other languages
English (en)
French (fr)
Inventor
Laurent Pelissier
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.)
Etudes et Constructions Mecaniques SA
Original Assignee
Etudes et Constructions Mecaniques SA
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 Etudes et Constructions Mecaniques SA filed Critical Etudes et Constructions Mecaniques SA
Publication of EP1101826A1 publication Critical patent/EP1101826A1/de
Withdrawn legal-status Critical Current

Links

Images

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
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/0062—Heat-treating apparatus with a cooling or quenching zone
    • 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
    • C21D1/56—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering characterised by the quenching agents
    • C21D1/613—Gases; Liquefied or solidified normally gaseous material
    • 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
    • C23C8/80—After-treatment

Definitions

  • the present invention relates to the treatment of parts steel, and more particularly the hardening of parts which have undergone heat treatments, in particular case hardening, that is to say introduction of carbon into the surface of the parts in order to improve hardness.
  • the invention relates more particularly quenching of parts having undergone a case hardening treatment vacuum or under low gas pressure (below pressure atmospheric).
  • a low pressure carburizing treatment consists of to submit the parts to be treated, in a sealed enclosure to the air, alternating enrichment stages in the presence a low pressure carburizing gas and diffusion steps vacuum or neutral atmosphere at low pressure.
  • the respective durations of enrichment and dissemination stages as well as their number depend in particular on the concentration in carbon and depth of cementation desired in the parts, and these treatments are well known in the art.
  • a example of low pressure carburizing process is described in French patent application No. 2,678,287 of the applicant.
  • Any cementation treatment is followed by at least one quenching step carried out either under oil or under gas.
  • a main purpose of quenching is to get cooling rapid hardened parts without altering the surface finish got.
  • Gas quenching is often preferred because it allows obtain dry and clean parts directly. We are looking for usually to get the most cooling speed fast possible. To increase the quenching speed with a given gas, we must increase the mass flow rate of the gas, i.e. increase the speed and / or static pressure of the gas quenching.
  • nitrogen conventionally constitutes an acceptable compromise in terms of cost and performance. Nitrogen is often preferred over gases neutrals such as helium and hydrogen which, although more light, therefore easier to transport under relatively pressure high, too expensive (helium) or too dangerous (hydrogen).
  • a disadvantage of using a gas such as nitrogen or other is, in addition to the cost, the need for transportation and storage of large volumes. Indeed, the speakers of industrial gas quenching often have volumes of several cubic meters, or even several tens of cubic meters.
  • quenching should not affect the hardness of the surface of the hardened part.
  • quenching must be rapid to satisfy the rapid cooling of the room and not degrade its surface.
  • we must most often satisfy to an imperative of appearance of the part obtained which, not only must generally present a surface state without roughness, but also be the color of the steel (gray). In particular, it is generally considered unacceptable that a part has a blackened appearance, suggesting an oxidation.
  • the invention also refers to carbonitriding whose only difference compared to the case hardening comes from enrichment gas used to which is generally added ammonia.
  • enrichment gas used to which is generally added ammonia The perfectly known result is the formation of nitrides (instead of carbides for cementation) on the surface of the room. It will therefore be noted that all that will be exposed subsequently in connection with case hardening also applies to carbonitriding.
  • An object of the present invention is to provide a new quenching process which overcomes the disadvantages of the processes known.
  • the invention aims, in particular, to allow the realization a particularly economical quenching treatment.
  • Another object of the invention is to propose a method which is compatible with conventional treatments of carburizing at low pressure.
  • Another object of the invention is to propose a method which respects the surface appearance of the finished parts.
  • the present invention provides a process for tempering treated steel parts low pressure thermal, which consists in subjecting the parts to a high pressure air flow.
  • the air pressure is between 5 and 50 bars.
  • the quenching time is less than 15 minutes and, preferably, less than 2 minutes.
  • parts are not released to air at atmospheric pressure between the low pressure heat treatment and the air quenching under high pressure.
  • the invention also provides a method of treatment parts comprising a low pressure carburizing treatment, followed by a quenching step.
  • cementation treatment includes alternating steps enrichment at low pressure in the presence of a carburizing and diffusion stages in the presence of a neutral gas at substantially the same pressure as the enrichment steps.
  • the parts are subjected, after the quenching step, to a shot blasting step to, in particular, remove the roughness of unwanted surface.
  • the invention further provides a treatment installation thermal comprising means for the implementation of the above processing method.
  • the installation includes several clean treatment cells to be sealed from the outside, and means for handling to transfer a load from one cell to another, one of these cells constituting a quenching cell specific to be further isolated from the rest of the installation for setting up work of an air quenching.
  • the quenching cell also serves as an unloading cell for the load at the end of treatment.
  • a feature of the present invention is provide quenching under air flow of parts having undergone carburizing or carbonitriding operation at low pressure. According to the invention, this quenching in air is carried out under high pressure (greater than 5 bars).
  • Oxidation of the part changes its hardness and makes its surface grainy.
  • a ventilation of the room for the whole the duration of the heat treatments has the effect of blackening its surface by oxidation, which was considered unacceptable from the point of view of the appearance of the room.
  • the present invention provides, unlike all of these prejudices, to use air for the gas quenching of the room case-hardened.
  • this air is used under high pressure (greater than 5 bars and, preferably between 5 and 50 bars).
  • Another advantage of the present invention is that the air can be used with very high pressures without difficulty.
  • the fact of using a high pressure makes it possible to shorten the duration of the quenching step since the mass flow is improved.
  • the duration of the air quenching step is limited to a few minutes (typically, less than 15 minutes) and is preferably less 2 minutes. The shorter the duration, the more the thickness of the surface oxidation of the part is low. Note that the finding the highest possible pressure is compatible with the search for a minimum duration.
  • the oxidation thickness linked to the presence of air during quenching is limited to a few micrometers. Such a thickness is negligible compared to the carburizing thicknesses generally carried out (from several hundred micrometers to a few millimeters).
  • this blasting step aims to eliminate burrs and surface irregularities related to the molding, forging or machining of parts and that is easier to remove after case hardening due to the more great hardness of the part.
  • this step eliminates also the few micrometers of oxidation linked to quenching under air. We thus find the metallic aspect of the surface of the part as at the end of a conventional quenching under nitrogen.
  • Figures 1A and 1B show the respective developments pressure and temperature during a mode implementing the heat treatment process of the invention, applied to an example of processing a grade steel 20MnCr5.
  • a load consisting of a batch of toothed crowns representing a total weight of 300 to 350 kg is introduced into a cementation treatment installation at low pressure.
  • a content 0.36% carbon up to 700 ⁇ m deep.
  • the charge, introduced at room temperature Tamb (Figure 1B) in the installation, is first brought to a temperature Tcem from 920 to 1000 ° C in 1 to 2 hours (instants t0 to t1).
  • Tcem room temperature
  • the pressure is lowered to a Pcem value of 5 to 20 mbar ( Figure 1A).
  • the load is subjected to five enrichment stages (E) under carbon atmosphere, alternated with as many diffusion stages (D) under nitrogen.
  • the respective durations of the enrichment stages and of diffusion are chosen in a conventional way and are, of preferably decreasing for the enrichment stages (by example, respectively, of approximately 5 min, 2 min, 1 min 40 s, 1 min 35 s and 1 min 30 s) and increasing for the diffusion stages (e.g., approximately 5 min, 10 min, 15 min, respectively, 25 min and 40 min).
  • the total duration of the carburizing step is, for example, around 97 min (instants t1 to t2) and we obtain, in end of carburizing, a carbon content greater than 0.36% up to a depth of 775 ⁇ m.
  • the load is then subjected to a quenching according to the invention (instants t3 to t4) under an air pressure Ptrem of approximately 16 bars for 30 seconds.
  • a quenching according to the invention instants t3 to t4
  • Ptrem air pressure
  • the case hardening steps and quenching are carried out in separate cells. This is why, in FIG. 1A, we have indicated a time of transfer (T, instants t2 to t3) from the cementation cell to the quenching cell.
  • T time of transfer
  • a steel is obtained having a surface hardness of 62-64 Hrc and a hardness of feet 300-320 HV20 tooth.
  • the quenching step has the effect of oxidizing the surface on a thickness of less than 5 ⁇ m. Besides that this depth is too weak to influence the hardness of the part, it is preferably eliminated by a shot blasting step implemented later outside the enclosure. Note that the depths carbon diffusion are usually planned with a margin allowing the shot peening to leave a thickness conforms to that intended. Thus, the invention does not require extend the enrichment and dissemination stages to increase cementation depth to account for the low oxidation.
  • FIG. 2 represents an exemplary embodiment of a treatment installation adapted to the implementation of a treatment air quenching according to the invention.
  • the embodiment of figure 2 is inspired by a modular installation such as described in European patent application No. 0 922 778 of the Applicant to whom we can refer for further information details.
  • a basic module 6 includes a sealed enclosure 10 in the form of a cylinder (not necessarily circular in cross-section) with horizontal axis. The two ends of this cylinder 10, provided flanges, are sealed with removable waterproof covers 12. Treatment cells are connected laterally to the cylinder 10 and lie in the same horizontal plane. Through example, two heat treatment cells 14 (for example, to contain two charges to be cemented) are arranged one in facing each other by being connected to a first transfer case 10-1 constituting the cylinder 10. A loading-unloading cell 15 is arranged opposite a quenching cell 16, these cells being connected to a second transfer case 10-2, itself axially connected to the box 10-1.
  • a handling device is in the form of a carriage 18 moving parallel to the axis of the cylinder 10, from one transfer case to another.
  • This carriage moves, by example, on rails 20 extending all along the cylinder 10.
  • the carriage is provided with a telescopic fork 22 which is capable of to stretch on either side of the carriage 18 to the center from each of cells 14 to 16 to pick up and drop off a load 24 being processed.
  • the carriage 18 in lines full, the carriage 18 is located at cells 15 and 16, and the telescopic fork 22 enters the cell 15 to there take charge 24.
  • cell 15 has been previously setting the enclosure 10 to low pressure to be able to open door 15-1 which constitutes, with the exterior door 15-2, an entrance airlock.
  • the carriage 18 is located at level of cells 14.
  • An installation as illustrated in Figure 2 is modular, i.e. one or more modules additional 8 each consisting of a transfer case 10-3 provided with 20 'rails and one or two 14' cells can be axially connected to one of the boxes 10-1 or 10-2 to complete cylinder 10.
  • the quench cell is also a cementation cell.
  • provision may be made for the cell quenching system constitutes the exit airlock of an installation multicellular.
  • the quenching step is generally the last stage of treatment within the installation.
  • this is compatible with the quenching of a charge at the same time as the case hardening of one or several subsequent charges.
  • the only change to make concerns the quenching cell (16, figure 1) to which then adapt an unloading door to the outside.
  • the present invention is capable of various variants and modifications which will appear to the man of art.
  • the invention has been described in relationship with low pressure carburizing treatment, it more generally applies to any processing in which similar problems arise, in particular in which one today provides for quenching under neutral gas, under nitrogen or similar, following treatment at low pressure. He will be able to for example, carbonitriding, brazing and others partial vacuum applications before quenching.
  • the adaptation of the implementation data of the quenching method of the invention depending on the type of parts, of the load volume, and previous treatments is at the scope of the skilled person from the indications given above.
  • the figures given of the particular example indicated above have only one virtue illustrating the feasibility of the invention, and that others values may be adopted including for the treatment of this type of steel.
  • the composition of the air is generally not critical. Indeed, the compositions of atmospheric air from different parts of the world are few different (at least with regard to the compounds of interest invention) and in most cases do not require, no particular adaptation.
  • the air used is, however, filtered to avoid introducing impurities into the installation.
  • the air will be dried if necessary to reduce the risks of oxidation.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Heat Treatment Of Articles (AREA)
EP00410142A 1999-11-17 2000-11-16 Abschreckverfahren nach Niederdruck-Aufkohlung Withdrawn EP1101826A1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR9914449A FR2801059B1 (fr) 1999-11-17 1999-11-17 Procede de trempe apres cementation a basse pression
FR9914449 1999-11-17
US09/715,525 US6451137B1 (en) 1999-11-17 2000-11-17 Method of quenching after a low-pressure carburization

Publications (1)

Publication Number Publication Date
EP1101826A1 true EP1101826A1 (de) 2001-05-23

Family

ID=26235159

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00410142A Withdrawn EP1101826A1 (de) 1999-11-17 2000-11-16 Abschreckverfahren nach Niederdruck-Aufkohlung

Country Status (3)

Country Link
US (1) US6451137B1 (de)
EP (1) EP1101826A1 (de)
FR (1) FR2801059B1 (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2826374A1 (fr) * 2001-06-21 2002-12-27 Serthel Procede et dispositif de trempe des aciers a l'air sous pression
WO2016075377A1 (fr) * 2014-11-14 2016-05-19 Peugeot Citroen Automobiles Sa Procédé et installation de carbonitruration de pièce(s) en acier sous basse pression et haute température
FR3081884A1 (fr) * 2018-06-05 2019-12-06 Safran Helicopter Engines Procede de cementation basse pression d'une piece comprenant de l'acier

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4698921B2 (ja) * 2002-01-22 2011-06-08 出光興産株式会社 焼入れ方法
US20050193743A1 (en) * 2004-03-05 2005-09-08 John Foss High-pressure cryogenic gas for treatment processes
FR2874079B1 (fr) * 2004-08-06 2008-07-18 Francis Pelissier Machine de traitement thermochimique de cementation
US20070068601A1 (en) * 2005-09-26 2007-03-29 Jones William R Process for treating steel alloys
FR2917752B1 (fr) * 2007-06-22 2019-06-28 Montupet Sa Procede de traitement thermique de pieces de fonderie mettant en oeuvre une trempe a l'air et systeme pour la mise en oeuvre du procede
FR2917751B1 (fr) * 2007-06-22 2011-04-01 Montupet Sa Procede de traitement thermique de culasses en alliage a base d'aluminuim, et culasses presentant des proprietes de resistance a la fatigue ameliorees
US9822422B2 (en) 2009-09-24 2017-11-21 Ati Properties Llc Processes for reducing flatness deviations in alloy articles
US8425691B2 (en) 2010-07-21 2013-04-23 Kenneth H. Moyer Stainless steel carburization process
JP6297471B2 (ja) * 2014-11-10 2018-03-20 中外炉工業株式会社 熱処理設備
FR3032205B1 (fr) * 2015-02-04 2017-02-17 Peugeot Citroen Automobiles Sa Installation de carbonitruration en serie de piece(s) en acier sous basse pression et haute temperature

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3736501C1 (de) * 1987-10-28 1988-06-09 Degussa Verfahren zur Waermebehandlung metallischer Werkstuecke
FR2678287A1 (fr) * 1991-06-26 1992-12-31 Etudes Const Mecaniques Procede et four de cementation a basse pression.
DE4208485C1 (de) * 1992-03-17 1993-02-11 Joachim Dr.-Ing. 7250 Leonberg De Wuenning
FR2771754A1 (fr) * 1997-12-02 1999-06-04 Etudes Const Mecaniques Installation de traitement thermique sous vide modulaire

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3736501C1 (de) * 1987-10-28 1988-06-09 Degussa Verfahren zur Waermebehandlung metallischer Werkstuecke
FR2678287A1 (fr) * 1991-06-26 1992-12-31 Etudes Const Mecaniques Procede et four de cementation a basse pression.
DE4208485C1 (de) * 1992-03-17 1993-02-11 Joachim Dr.-Ing. 7250 Leonberg De Wuenning
FR2771754A1 (fr) * 1997-12-02 1999-06-04 Etudes Const Mecaniques Installation de traitement thermique sous vide modulaire

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
ALTENA H: "NIEDERDRUCK-AUFKOHLUNG MIT HOCHDRUCK-GASABSCHRECKUNG VERFAHRENSTECHNIK UND ERGEBNISSE", HAERTEREI TECHNISCHE MITTEILUNGEN,DE,CARL HANSER VERLAG. MUNCHEN, vol. 53, no. 2, 1 March 1998 (1998-03-01), pages 93 - 101, XP000755093, ISSN: 0341-101X *
HOFFMANN R ET AL: "MOEGLICHKEITEN UND GRENZEN DER GASABKUEHLUNG", HAERTEREI TECHNISCHE MITTEILUNGEN,DE,CARL HANSER VERLAG. MUNCHEN, vol. 47, no. 2, 1 March 1992 (1992-03-01), pages 112 - 122, XP000267300, ISSN: 0341-101X *
TINSCHER R ET AL: "FIXTURHAERTUNG VON WAELZLAGERRINGEN UNTER VERWENDUNG VON GASFOERMIGEN ABSCHRECKMEDIEN", HAERTEREI TECHNISCHE MITTEILUNGEN,DE,CARL HANSER VERLAG. MUNCHEN, vol. 53, no. 2, 1 March 1998 (1998-03-01), pages 108 - 115, XP000755095, ISSN: 0341-101X *

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2826374A1 (fr) * 2001-06-21 2002-12-27 Serthel Procede et dispositif de trempe des aciers a l'air sous pression
WO2003000939A1 (fr) * 2001-06-21 2003-01-03 Serthel Procede et dispositif de trempe des aciers a l'air pression
WO2016075377A1 (fr) * 2014-11-14 2016-05-19 Peugeot Citroen Automobiles Sa Procédé et installation de carbonitruration de pièce(s) en acier sous basse pression et haute température
FR3028530A1 (fr) * 2014-11-14 2016-05-20 Peugeot Citroen Automobiles Sa Procede et installation de carbonitruration de piece(s) en acier sous basse pression et haute temperature
US11512381B2 (en) 2014-11-14 2022-11-29 Ecm Technologies Sas Method and facility for carbonitriding one or more steel parts under low pressure and at a high temperature
FR3081884A1 (fr) * 2018-06-05 2019-12-06 Safran Helicopter Engines Procede de cementation basse pression d'une piece comprenant de l'acier
WO2019234352A1 (fr) * 2018-06-05 2019-12-12 Safran Helicopter Engines Procédé de cémentation basse pression d'une pièce comprenant de l'acier
US11293087B2 (en) 2018-06-05 2022-04-05 Safran Helicopter Engines Method for low-pressure carburizing of a workpiece comprising steel

Also Published As

Publication number Publication date
US6451137B1 (en) 2002-09-17
FR2801059A1 (fr) 2001-05-18
FR2801059B1 (fr) 2002-01-25

Similar Documents

Publication Publication Date Title
FR2801059A1 (fr) Procede de trempe apres cementation a basse pression
EP1885904B1 (de) Niederdruckcarbonitrierverfahren und -vorrichtung
KR100301677B1 (ko) 티타늄또는티타늄합금부재와그표면처리방법
EP2167693B1 (de) Verfahren zur wärmebehandlung von gussteilen unter verwendung einer luftabschreckung und system zur durchführung des verfahrens
EP3218530B1 (de) Verfahren und anlage zur karbonitrierung einer oder mehrerer stahlteile unter niedrigem druck und bei hoher temperatur
CA2715174C (fr) Procede de revetement d'une bande metallique et installation de mise en oeuvre du procede
FR2624882A1 (fr) Procede de revetement de pieces en alliages de titane par de l'aluminium diffuse
EP1105247B1 (de) Verfahren zum verbinden von martensitischem rostfreiem stahl mit einer kupferlegierung durch diffusionsschweissen und so hergestelltes bimetallisches element
EP1167549A1 (de) Gasabschreckkammer
CA2970247C (fr) Procede et four de carbonitruration a basse pression
FR2576916A1 (fr) Procede de formation en phase gazeuse constamment renouvelee, sous pression reduite, de revetements protecteurs sur des pieces en alliages refractaires, et dispositif pour sa mise en oeuvre
EP2732066B1 (de) Verfahren zur abkühlung von in einer salzschmelze nitririerten oder karbonitririerten metallischen teilen, vorrichtung dafür und demnach behandelte teilen
FR3058423A1 (fr) Procede de traitement thermique d'une piece en acier fortement allie
EP0737755B1 (de) Verfahren und Vorrichtung zur Wärmebehandlung von Werkstücken
EP0067098B1 (de) Verfahren zur Ionisierung eines Werkstückes aus Stahl, das zuvor plastisch verformt wurde
EP1404882B1 (de) Verfahren zum abschrecken von stahl mittels druckluft
WO2018128160A1 (ja) 合金部材およびその表面硬化方法
FR2863629A1 (fr) Procede et dispositif de traitement physicochimique a chaud de pieces mecaniques
EP3287857A1 (de) Herstellungsverfahren eines artikels auf zirkonbasis, der ein metallisches aussehen hat
FR2867607A1 (fr) Procede de fabrication d'un substrat pour la microelectronique, l'opto-electronique et l'optique avec limitaton des lignes de glissement et substrat correspondant
JPH11264063A (ja) チタン装飾部材の硬化処理方法
CH269520A (fr) Procédé pour le revêtement d'objets en métal par des couches d'un métal différent.
FR2792339A1 (fr) Procede et dispositif de carburation sous vide en continu
WO2020099794A1 (fr) Procédé de décapage d'une pièce de turbomachine
EP0524160A2 (de) Verfahren zur Herstellung von Hartstahldraht

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

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES FR GB IT

AX Request for extension of the european patent

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

17P Request for examination filed

Effective date: 20011119

AKX Designation fees paid

Free format text: DE ES FR GB IT

17Q First examination report despatched

Effective date: 20040212

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

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20050113