EP0570421A1 - Process for producing a surface-hardened workpiece of sintered iron. - Google Patents

Process for producing a surface-hardened workpiece of sintered iron.

Info

Publication number
EP0570421A1
EP0570421A1 EP92903727A EP92903727A EP0570421A1 EP 0570421 A1 EP0570421 A1 EP 0570421A1 EP 92903727 A EP92903727 A EP 92903727A EP 92903727 A EP92903727 A EP 92903727A EP 0570421 A1 EP0570421 A1 EP 0570421A1
Authority
EP
European Patent Office
Prior art keywords
workpiece
mbar
steam treatment
treatment
water vapor
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
EP92903727A
Other languages
German (de)
French (fr)
Other versions
EP0570421B1 (en
Inventor
Rudolf Schneider
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.)
Robert Bosch GmbH
Original Assignee
Robert Bosch 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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP0570421A1 publication Critical patent/EP0570421A1/en
Application granted granted Critical
Publication of EP0570421B1 publication Critical patent/EP0570421B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/24—After-treatment of workpieces or articles
    • 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
    • C23C8/02—Pretreatment of the material to be coated
    • 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
    • C23C8/10—Oxidising
    • C23C8/16—Oxidising using oxygen-containing compounds, e.g. water, carbon dioxide
    • C23C8/18—Oxidising 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
    • C23C8/34—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 more than one step

Definitions

  • the invention relates to a method for producing a
  • DE-OS 33 01 541 proposes the porous workpiece made of sintered iron to produce
  • liquid substances can penetrate into the porous workpiece. Reactions with corrosive agents or the like then occur, the property of the workpiece surface being changed. In order to prevent the penetration of such substances into the surface of a porous workpiece, it is known to coat it with synthetic resin, wax, oily substance or the like.
  • the porosity of sintered workpieces is also disadvantageous when it comes to hardening the surface layer. Through the pores, the gases used for hardening can enter the interior of the
  • Heat treatment is primarily used to achieve greater hardness.
  • As a heat treatment process carburizing,
  • Nitrocarburizing, nitriding and oxidizing are known. Through this
  • the steam treatment is carried out in accordance with the features of claim 1 in such a way that a sufficient pore closure with the least possible
  • Oxide layer density is reached. Surprisingly, these properties can be obtained even at relatively low water vapor temperatures. This results in an economic one
  • the modified water vapor treatment preferably produces an oxide layer of at most 5 ⁇ m, preferably of ⁇ 4 ⁇ m, on the surface of the workpiece. This is done by targeted steam treatment at the specified temperatures and pressures of the superheated steam. The goal is a sufficient pore closure with a minimal oxide layer thickness.
  • the workpiece is in front of the
  • the mechanical processing is preferably carried out by vibratory grinding or by lapping. Mechanical processing is particularly recommended when tight tolerances are specified for dimensional accuracy or when a well-defined layer with tight tolerances is required. Following the mechanical processing, the workpiece is subjected to surface hardening.
  • the above-mentioned method is mainly used in the production of ring gears, with a significantly improved one
  • a ring gear hardened by nitrocarburizing is produced in the following production stages:

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Powder Metallurgy (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

Selon un procédé de fabrication d'une pièce en métal fritté, notamment du fer fritté, celle-ci est soumise après le frittage à un traitement à la vapeur d'eau à des températures inférieures à 500 °C, notamment comprises entre 430 et 480 °C, sous une pression partielle de vapeur d'eau comprise entre 20 et 80 mbars, notamment entre 30 et 50 mbars, ainsi qu'à une trempe ultérieure des couches marginales, afin de former une couche d'oxyde à la surface de la pièce. On obtient ainsi des pièces, notamment des roues à dentures intérieures pour démarreurs, ayant une surface résistante à l'usure et un noyau dont les propriétés ne sont pas affectées par la trempe.According to a method of manufacturing a sintered metal part, in particular sintered iron, the latter is subjected after sintering to a treatment with water vapor at temperatures below 500 ° C, in particular between 430 and 480 ° C, under a partial pressure of water vapor of between 20 and 80 mbar, in particular between 30 and 50 mbar, as well as a subsequent quenching of the marginal layers, in order to form an oxide layer on the surface of the room. Parts are thus obtained, in particular internally toothed wheels for starters, having a wear-resistant surface and a core whose properties are not affected by hardening.

Description

Verfahren zum Herstellen eines oberflächengehärteten Werkstückes aus Sintereisen  Process for producing a surface hardened workpiece from sintered iron
Stand der Technik State of the art
Die Erfindung betrifft ein Verfahren zum Herstellen eines The invention relates to a method for producing a
oberflächengehärteten Werkstückes aus Sintereisen, wobei nach dem Sintern durch eine Wasserdampfbehandlung die Poren an der Oberfläche weitgehend geschlossen werden und das Werkstück anschließend einer Randschichtenhärtung unterzogen wird. Surface-hardened workpiece made of sintered iron, the pores on the surface being largely closed after the sintering by means of a steam treatment and the workpiece subsequently being subjected to surface layer hardening.
Aus der DE-OS 33 01 541 ist ein gattungsgemäßes Verfahren bekannt. Zum Zweck des Porenverschlusses als Vorbehandlung für eine A generic method is known from DE-OS 33 01 541. For the purpose of pore closure as a pretreatment for a
Oberflächenhärtung erfolgt dabei eine Wasserdampfbehandlung. Zur Verbesserung der Maßhaltigkeit schlägt die DE-OS 33 01 541 vor, das poröse Werkstück aus gesintertem Eisen zur Erzeugung von Surface hardening is carried out using a steam treatment. To improve the dimensional accuracy, DE-OS 33 01 541 proposes the porous workpiece made of sintered iron to produce
Eisenoxidschichten auf den zugänglichen inneren und äußeren Iron oxide layers on the accessible inner and outer
Oberflächen in einer wasserdampfhaltigen Atmosphäre und in einer zweiten Stufe zur teilweisen Reduktion dieser Oxidschichten und zur Härtung einer schmalen, von der äußeren Oberfläche ausgehenden Zone in Gegenwart eines Kohlenstoff abgebenden Fluids erhitzt wird. Surfaces in a water vapor-containing atmosphere and in a second stage to partially reduce these oxide layers and to harden a narrow zone emanating from the outer surface in the presence of a carbon-donating fluid.
Allerdings ist die Steuerung dieses Verfahrens und damit auch die Steuerung der Bildung beziehungsweise Reduktion der Oxidschicht sehr beschränkt. Die aus einem Sintereisen, das heißt pulvermetallurgisch However, the control of this method and thus also the control of the formation or reduction of the oxide layer is very limited. That from a sintered iron, that means powder metallurgy
hergestellten Werkstücke sind im allgemeinen porös, sofern sie nicht durch Schmieden oder andere Formungsverfahren verdichtet werden. Die Porosität hat jedoch Nachteile, zum Beispiel in Bezug auf die  Workpieces made are generally porous unless they are compacted by forging or other molding processes. However, the porosity has disadvantages, for example in relation to the
Korrosionsbeständigkeit, welche beeinträchtigt ist, da  Corrosion resistance, which is impaired because
beispielsweise flüssige Stoffe in das poröse Werkstück eindringen. Hier kommt es dann zu Reaktionen mit korrodierenden Agenzien oder dergleichen, wobei die Eigenschaft der Werkstückoberfläche verändert wird. Zur Verhinderung des Eindringens derartiger Stoffe in die Oberfläche eines porösen Werkstückes ist es bekannt, dieses mit Kunstharz, Wachs, ölartiger Substanz oder dergleichen zu überziehen.  for example, liquid substances can penetrate into the porous workpiece. Reactions with corrosive agents or the like then occur, the property of the workpiece surface being changed. In order to prevent the penetration of such substances into the surface of a porous workpiece, it is known to coat it with synthetic resin, wax, oily substance or the like.
Die Porosität gesinterter Werkstücke ist außerdem nachteilig, wenn es darum geht, eine Randschichtenhärtung zu erzielen. Durch die Poren können die zur Härtung eingesetzten Gase ins Innere des The porosity of sintered workpieces is also disadvantageous when it comes to hardening the surface layer. Through the pores, the gases used for hardening can enter the interior of the
Werkstückes eindringen, wobei das Werkstück durchhärtet. Um  Penetrate the workpiece, whereby the workpiece hardens. Around
ausschließlich eine Randschichtenhärtung zu erreichen, ist daher ein weitgehender und im Härtungsprozeß stabiler Porenverschluß  To achieve only surface hardening is therefore an extensive and stable pore seal in the hardening process
notwendig. Die oben beschriebenen Überzüge sind allerdings  necessary. However, the coatings described above are
unbeständig, so daß eine entsprechende Imprägnierung nicht für gesinterte Werkstücke brauchbar ist, die nach dem Sintern einer Wärmebehandlung unterworfen sind.  inconsistent, so that a corresponding impregnation is not useful for sintered workpieces that are subjected to a heat treatment after sintering.
Eine Wärmebehandlung erfolgt vor allem zur Erzielung einer größeren Härte. Als Wärmebehandlungsverfahren sind ein Aufkohlen, Heat treatment is primarily used to achieve greater hardness. As a heat treatment process, carburizing,
Nitrocarburieren, Nitrieren und Oxidieren bekannt. Durch diese Nitrocarburizing, nitriding and oxidizing are known. Through this
Verfahren lassen sich Oberflächen von hoher Verschleißfestigkeit erzielen. Vorteile der Erfindung Processes can achieve surfaces with high wear resistance. Advantages of the invention
Nach der vorliegenden Erfindung wird die Wasserdampfbehandlung entsprechend den Merkmalen von Anspruch 1 so geführt, daß ein ausreichender Porenverschluß bei geringst möglicher According to the present invention, the steam treatment is carried out in accordance with the features of claim 1 in such a way that a sufficient pore closure with the least possible
Oxidschichtdichte erreicht wird. Überraschenderweise können diese Eigenschaften bereits bei relativ niedrigen Wasserdampftemperaturen erhalten werden. Daraus ergibt sich eine wirtschaftliche  Oxide layer density is reached. Surprisingly, these properties can be obtained even at relatively low water vapor temperatures. This results in an economic one
Arbeitsweise bei zumindest gleichbleibend guten Ergebnissen.  Working method with at least consistently good results.
Ein weiterer Vorteil der niedrigeren Wasserdampftemperaturen ergibt sich daraus, daß die Bildung von FeO vermieden wird, die ab etwa 560° C eintritt. FeO zerfällt bei Abkühlung in Fe3O4 und Fe; Another advantage of the lower water vapor temperatures results from the fact that the formation of FeO is avoided, which occurs from about 560 ° C. FeO decomposes into Fe 3 O 4 and Fe on cooling;
dieser Zerfall führt zu einer schwammigen Oberflächenstruktur, die neben einer deutlich verminderten Korrosionsbeständigkeit auch zu einer voluminösen Verbindungsschicht bei der nachfolgenden  this decay leads to a spongy surface structure which, in addition to a significantly reduced corrosion resistance, also leads to a voluminous connecting layer in the subsequent one
Wärmebehandlung, somit insbesondere zur Verschlechterung der Heat treatment, in particular to worsen the
Maßhaltigkeit führt. Dimensional accuracy leads.
Bevorzugt wird durch die modifizierte Wasserdampfbehandlung eine Oxidschicht von maximal 5 μm, vorzugsweise von < 4 μm , auf der Oberfläche des Werkstücks hergestellt. Dies geschieht durch ein gezieltes Wasserdampfbehandeln bei den angegebenen Temperaturen und Drücken des überhitzten Wasserdampfes. Ziel ist ein auseichender Porenverschluß bei minimaler Oxidschichtdicke. The modified water vapor treatment preferably produces an oxide layer of at most 5 μm, preferably of <4 μm, on the surface of the workpiece. This is done by targeted steam treatment at the specified temperatures and pressures of the superheated steam. The goal is a sufficient pore closure with a minimal oxide layer thickness.
Gemäß einem Ausführungsbeispiel wird das Werkstück vor der According to one embodiment, the workpiece is in front of the
Wasserdampfbehandlung einer mechanischen Bearbeitung unterzogen. Die mechanische Bearbeitung erfolgt dabei bevorzugt durch Gleitschleifen oder durch Läppstrahlen. Die mechanische Bearbeitung empfiehlt sich vor allem, wenn enge Toleranzen bei der Maßhaltigkeit vorgegeben sind oder wenn eine gut ausgeprägte Schicht mit engen Toleranzen gefordert wird. Das Werkstück wird im Anschluß an die mechanische Bearbeitung einer Randschichthärtung unterzogen. Steam treatment subjected to mechanical processing. The mechanical processing is preferably carried out by vibratory grinding or by lapping. Mechanical processing is particularly recommended when tight tolerances are specified for dimensional accuracy or when a well-defined layer with tight tolerances is required. Following the mechanical processing, the workpiece is subjected to surface hardening.
Das oben genannte Verfahren wird vor allem bei der Herstellung von Hohlrädern verwendet, wobei sich eine deutlich verbesserte The above-mentioned method is mainly used in the production of ring gears, with a significantly improved one
Maßhaltigkeit herausstellte. Durch das Verfahren läßt sich der Ausschuß erheblich reduzieren, ein Vermessen ist nicht mehr notwendig. Dimensional accuracy. The method allows the committee to be reduced considerably, and measurement is no longer necessary.
In einem Ausführungsbeispiel wird ein durch Nitrocarburieren gehärtetes Hohlrad in folgenden Fertigungsstufen hergestellt: In one embodiment, a ring gear hardened by nitrocarburizing is produced in the following production stages:
Basispulver Graphit Gleitmittel Base powder graphite lubricant
↘ ↓ ↙  ↘ ↓ ↙
Mischen  Mix
↓  ↓
Pressen  Press
↓  ↓
Sintern  Sintering
↓  ↓
Gleitschleifen  Vibratory grinding
↓  ↓
Kalibrieren  Calibrate
↓  ↓
Wass Ierdampfbehandlung  Water vapor treatment
bei 430 - 480° C,  at 430 - 480 ° C,
30 - 50 mbar und 2 h  30 - 50 mbar and 2 h
↓  ↓
Nitrocarburieren  Nitrocarburizing

Claims

Ansprüche Expectations
1. Verfahren zum Herstellen eines Werkstückes aus Sintereisen, wobei nach dem Sintern zunächst die Poren an der Oberfläche des 1. A method for producing a workpiece from sintered iron, wherein after sintering, the pores on the surface of the
Werkstückes durch eine Behandlung mit überhitztem Wasserdampf weitgehend geschlossen werden und das Werkstück anschließend einer Randschichtenhärtung unterzogen wird, dadurch gekennzeichnet, daß die Wasserdampfbehandlung bei einer Temperatur unterhalb 500° C, insbesondere bei 430 bis 480° C, und bei einem  Workpiece are largely closed by treatment with superheated steam and the workpiece is then subjected to surface hardening, characterized in that the steam treatment at a temperature below 500 ° C, in particular at 430 to 480 ° C, and at a
Wasserdampfpartialdruck von 20 bis 80 mbar, insbesondere von 30 bis 50 mbar, erfolgt.  Water vapor partial pressure of 20 to 80 mbar, in particular 30 to 50 mbar.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die 2. The method according to claim 1, characterized in that the
Wasserdampfbehandlung bis maximal 2 Stunden durchgeführt wird. Steam treatment is carried out for a maximum of 2 hours.
3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß durch die Wasserdampfbehandlung eine Oxidschicht von maximal 5 μm, vorzugsweise von < 4 μm, auf der Oberfläche des Werkstückes hergestellt wird. 3. The method according to claim 1 or 2, characterized in that an oxide layer of at most 5 microns, preferably <4 microns, is produced by the steam treatment on the surface of the workpiece.
4. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Werkstücke vor der Wasserdampfbehandlung einer mechanischen Bearbeitung unterzogen werden. 4. The method according to any one of the preceding claims, characterized in that the workpieces are subjected to mechanical processing before the steam treatment.
5. Verfahren nach Anspruch 4, dadurch gekennzeichnet, daß die mechanische Bearbeitung durch Schleifen oder Läppen erfolgt. 5. The method according to claim 4, characterized in that the mechanical processing is carried out by grinding or lapping.
6. Verwendung des Verfahrens nach einem der Ansprüche 1 bis 6 zur Herstellung von Vorgelegeradern für Starter, insbesondere von innenverzahnten Hohlrädern. 6. Use of the method according to one of claims 1 to 6 for the production of countershaft for starters, in particular of internally toothed ring gears.
7. Verwendung des Verfahrens nach einem der Ansprüche 1 bis 6 zur Herstellung von Grundplatte und/oder Stützplatte von 7. Use of the method according to one of claims 1 to 6 for the production of base plate and / or support plate of
Elektrokraftstoffpumpen. Electric fuel pumps.
EP92903727A 1991-02-07 1992-02-06 Process for producing a surface-hardened workpiece of sintered iron Expired - Lifetime EP0570421B1 (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE4103692 1991-02-07
DE4140148 1991-12-05
DE4140148A DE4140148A1 (en) 1991-02-07 1991-12-05 METHOD FOR PRODUCING A SURFACE-HARDENED WORKPIECE FROM SINTER IRON
PCT/DE1992/000074 WO1992013666A1 (en) 1991-02-07 1992-02-06 Process for producing a surface-hardened workpiece of sintered iron
DE4103692 1992-02-07

Publications (2)

Publication Number Publication Date
EP0570421A1 true EP0570421A1 (en) 1993-11-24
EP0570421B1 EP0570421B1 (en) 1995-08-02

Family

ID=25900829

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92903727A Expired - Lifetime EP0570421B1 (en) 1991-02-07 1992-02-06 Process for producing a surface-hardened workpiece of sintered iron

Country Status (6)

Country Link
US (1) US5383979A (en)
EP (1) EP0570421B1 (en)
JP (1) JPH06504814A (en)
KR (1) KR930703105A (en)
DE (2) DE4140148A1 (en)
WO (1) WO1992013666A1 (en)

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Publication number Priority date Publication date Assignee Title
DE19917605B4 (en) * 1999-04-19 2005-10-27 Renk Ag Transmission for wind generators
US6623237B2 (en) * 2001-08-21 2003-09-23 Delphi Technologies, Inc. Wear resistant fuel pump
JP5731107B2 (en) * 2009-07-01 2015-06-10 本田技研工業株式会社 Nitriding member and manufacturing method thereof
WO2013127905A1 (en) * 2012-02-29 2013-09-06 Höganäs Ab (Publ) Pm automotive component and its manufacture
DE102012219949A1 (en) 2012-10-31 2014-04-30 Schaeffler Technologies Gmbh & Co. Kg Rotor of a camshaft adjuster, camshaft adjuster with such a rotor and method for manufacturing a rotor
AT517751B1 (en) * 2015-09-29 2018-04-15 Miba Sinter Austria Gmbh Process for producing a sintered gear
DE102016122826A1 (en) 2016-11-25 2018-05-30 Schaeffler Technologies AG & Co. KG The wave gear

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JPS583901A (en) * 1981-07-01 1983-01-10 Toyota Motor Corp Manufacture of sliding member
DE3301541A1 (en) * 1983-01-19 1984-07-19 Ringsdorff-Werke GmbH, 5300 Bonn Process for the production from surface-hardened sintered bodies
JPH0713242B2 (en) * 1985-04-30 1995-02-15 住友電気工業株式会社 Surface treatment method for sintered machine parts
US4738730A (en) * 1986-02-18 1988-04-19 Lindberg Corporation Steam sealing for nitrogen treated ferrous part
DE3806933A1 (en) * 1988-03-03 1989-11-30 Man Technologie Gmbh Process for producing oxide layers on steels

Non-Patent Citations (1)

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Title
See references of WO9213666A1 *

Also Published As

Publication number Publication date
DE59203117D1 (en) 1995-09-07
DE4140148A1 (en) 1992-08-13
EP0570421B1 (en) 1995-08-02
DE4140148C2 (en) 1993-03-18
WO1992013666A1 (en) 1992-08-20
US5383979A (en) 1995-01-24
JPH06504814A (en) 1994-06-02
KR930703105A (en) 1993-11-29

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