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WO2001049979A2 - Corps de soupape produit par metallurgie des poudres et soupape equipee dudit corps de soupape - Google Patents

Corps de soupape produit par metallurgie des poudres et soupape equipee dudit corps de soupape Download PDF

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Publication number
WO2001049979A2
WO2001049979A2 PCT/EP2001/000036 EP0100036W WO0149979A2 WO 2001049979 A2 WO2001049979 A2 WO 2001049979A2 EP 0100036 W EP0100036 W EP 0100036W WO 0149979 A2 WO0149979 A2 WO 0149979A2
Authority
WO
WIPO (PCT)
Prior art keywords
valve body
valve
body according
powder
powder metallurgy
Prior art date
Application number
PCT/EP2001/000036
Other languages
German (de)
English (en)
Other versions
WO2001049979A3 (fr
Inventor
Gerd Krüger
Hans-Joachim Kaschuba
Franz-Josef Schleifstein
Original Assignee
Bleistahl-Produktions Gmbh & Co. Kg
Volkswagen Aktiengesellschaft
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 Bleistahl-Produktions Gmbh & Co. Kg, Volkswagen Aktiengesellschaft filed Critical Bleistahl-Produktions Gmbh & Co. Kg
Priority to AU37274/01A priority Critical patent/AU3727401A/en
Priority to AT01909578T priority patent/ATE305084T1/de
Priority to AU23720/01A priority patent/AU2372001A/en
Priority to EP01909578A priority patent/EP1250518B1/fr
Priority to DE50107484T priority patent/DE50107484D1/de
Priority to US10/169,951 priority patent/US6712872B2/en
Publication of WO2001049979A2 publication Critical patent/WO2001049979A2/fr
Publication of WO2001049979A3 publication Critical patent/WO2001049979A3/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/02—Making ferrous alloys by powder metallurgy
    • C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
    • C22C33/0278—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5%
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/02—Making ferrous alloys by powder metallurgy
    • C22C33/0207—Using a mixture of prealloyed powders or a master alloy
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/02—Making ferrous alloys by powder metallurgy
    • C22C33/0207—Using a mixture of prealloyed powders or a master alloy
    • C22C33/0214—Using a mixture of prealloyed powders or a master alloy comprising P or a phosphorus compound
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/36—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.7% by weight of carbon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L3/00—Lift-valve, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces; Parts or accessories thereof
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L3/00—Lift-valve, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces; Parts or accessories thereof
    • F01L3/02—Selecting particular materials for valve-members or valve-seats; Valve-members or valve-seats composed of two or more materials
    • 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
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy

Definitions

  • the invention relates to a powder-metallurgically manufactured valve body with high temperature and wear resistance and a valve equipped therewith for internal combustion engines.
  • Intake and exhaust valves for internal combustion engines must meet high requirements for temperature resistance and wear resistance. Particularly in the case of highly compressed modern engines with multi-valve technology and electronic control, it has become increasingly a problem to find materials which can permanently cope with the high temperatures prevailing at the outlet. Accordingly, valves have become more and more complex to manufacture, which has had an impact on the material and processing costs.
  • valve seat - were provided with inductive seat hardening or seat armor. This should keep the wear within acceptable limits, taking into account that too With this technology, valve temperatures of 800 ° C - 900 ° C should not be exceeded. However, this is becoming increasingly difficult to maintain in modern engines.
  • valves and valve bodies have become extremely complicated, particularly when armor is used.
  • the valve body is first produced by heating, compressing, calibrating and rotating, to which a rod section is added by friction welding.
  • Other work steps include straightening, turning, grinding and cladding, grinding and heat treatment to the finished valve with seat armor.
  • the build-up welding can lead to errors, which results in an undesirably high reject rate.
  • valve bodies from a uniform material in as few steps as possible, the material ensuring the necessary wear resistance, service life and heat dissipation, and with a rod to a valve connect.
  • the invention is therefore based on the object to produce valve bodies for valves by powder metallurgy from a suitable material, in particular taking into account the production costs.
  • Seat armor should be dispensable and the valve or the valve body should have sufficient thermal conductivity for temperature control.
  • the valve body should be able to be butt-connected with a conventionally manufactured valve rod to a functional and permanent valve.
  • valve body manufactured by powder metallurgy which has the following composition by weight:
  • the invention further relates to valves manufactured with this valve body.
  • the metal powder used according to the invention is characterized in particular by a very high carbon, molybdenum and phosphorus content.
  • the carbon and phosphorus content cause the formation of temperature-resistant and wear-reducing carbide and phosphide phases, which give the material the necessary service life.
  • Chromium, vanadium and tungsten can be added to vary the range of properties, but are not absolutely necessary in particular for the production of valves and valve parts.
  • An appreciable sulfur content can serve as an internal lubricant, especially if it is MoS 2 , but is generally not necessary for valves and parts.
  • the valve body produced by powder metallurgy according to the invention can be produced by conventional press-sintering processes. This also includes hot isostatic pressing, although this is not absolutely necessary.
  • valve bodies according to the invention can be produced from the corresponding element powders.
  • finished alloy components for the production, for example a finished alloy steel component, a phosphorus-molybdenum steel, optionally MoS 2 and, if necessary, graphite, in each case in powder form.
  • metal powders of irregular shape produced by atomization processes which can give the pressed part produced therefrom a certain internal cohesion by means of teeth.
  • customary auxiliaries can be added, for example wax, in an amount of up to 1% by weight, based on the alloy powder.
  • Dendritic or spattery powders with an average diameter of less than 150 ⁇ m are preferably used, preferably less than 50 ⁇ m.
  • Carbon is expediently admixed as graphite with an average size of 10 ⁇ m or less, if not already sufficiently represented in the finished alloy powder.
  • the PMoFe steel powder, as can be used here, is described in WO-A-91/18123.
  • Powder composition with 0.5 to 2.0% carbon, 5.0 to 14% molybdenum, 0.2 to 1, 0% phosphorus, 0.1 to 1, 2% manganese, maximum 0.50% chromium and maximum 0, 40% sulfur. Other elements in this case are less than 2% represented, the rest is iron.
  • the composition is based on weight percent.
  • the finished valve body should have a density of at least 7.7 g / cm 3 .
  • valves or valve bodies according to the invention show high wear resistance even at the high temperatures and loads in the valve train, in particular for exhaust valves.
  • valve body is made of the materials described above.
  • the shaft is made conventionally, ie without powder metallurgy techniques, from a conventional material.
  • the valve body and valve rod are butted together. In the case of the butt fit, the connection by means of a friction welding process is preferred, although other joining processes can also be used.
  • valve bodies these have the advantage over conventional valve bodies that they consist of a uniform material, ie they do not require local modification in order to adapt them to the particular circumstances of a piston outlet of an internal combustion engine. In addition to advantages in terms of production technology, this also means that the product is less susceptible to faults and damage, both in the manufacturing and in the operating phase.
  • the valve bodies according to the invention are produced from the premixed or finished alloy powder as follows. First, the blank is pressed out of the powder with the aid of a conventional wax as a lubricant under customary pressing pressures to give moldings with a sufficient density. The pressure is expediently between 500 and 900 MPa. After pressing, the product is first dewaxed under a hydrogen-nitrogen protective gas atmosphere at a temperature of 500 to 750 ° C and then in an oven at a temperature of more than 900 ° C, preferably more than 1000 ° C, up to 1150 ° C, sintered. Pressures and temperatures essentially depend on the desired density of the molded part and on the composition of the metal powder. After cooling, the parts are left on and subjected to the necessary post-treatment steps.
  • valve body and valve stem according to the invention are made in separate work steps and then joined.
  • the valve body is manufactured using powder metallurgy, the stump conventionally. In this constellation, the body and shaft can be joined together by friction welding. After the joining step, the valve is reworked.
  • Fig. 1 shows a valve body 1, which is made by powder metallurgy and is provided for butt connection to a stem 2.
  • a sintered body made of sintered molybdenum-phosphor steel with a density of 6.9 g / cm 3 was obtained.
  • the molded body showed good wear resistance and a finely divided structure of various carbides in a tempered martensitic matrix with embedded solid lubricant under high surface loads.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Powder Metallurgy (AREA)
  • Taps Or Cocks (AREA)
  • Lift Valve (AREA)
  • Formation And Processing Of Food Products (AREA)
  • Secondary Cells (AREA)
  • Ceramic Capacitors (AREA)
  • Gears, Cams (AREA)

Abstract

La présente invention concerne un corps de soupape, produit par métallurgie des poudres, qui présente une grande résistance thermique et une grande résistance à l'usure. La composition, en poids, dudit corps de soupape est la suivante : 0,5 % à 2,0 % de C; 5,0 % à 16 % de Mo; 0,2 % à 1,0 % de P; 0,1 % à 1,4 % de Mn; 0 % à 5 % de Cr; 0 % à 5 % de S; 0 % à 7 % de W; 0 % à 3 % de V; < 2 % d'autres éléments et le reste Fe. La présente invention concerne également une soupape équipée dudit corps de soupape.
PCT/EP2001/000036 2000-01-06 2001-01-04 Corps de soupape produit par metallurgie des poudres et soupape equipee dudit corps de soupape WO2001049979A2 (fr)

Priority Applications (6)

Application Number Priority Date Filing Date Title
AU37274/01A AU3727401A (en) 2000-01-06 2001-01-04 Powder metallurgy produced valve body and valve fitted with said valve body
AT01909578T ATE305084T1 (de) 2000-01-06 2001-01-04 Pulvermetallurgisch hergestellter ventilkörper und damit ausgestattetes ventil
AU23720/01A AU2372001A (en) 2000-01-06 2001-01-04 Powder metallurgy produced press-sinter shaped part
EP01909578A EP1250518B1 (fr) 2000-01-06 2001-01-04 Corps de soupape produit par metallurgie des poudres et soupape equipee dudit corps de soupape
DE50107484T DE50107484D1 (de) 2000-01-06 2001-01-04 Pulvermetallurgisch hergestellter ventilkörper und damit ausgestattetes ventil
US10/169,951 US6712872B2 (en) 2000-01-06 2001-01-04 Powder metallurgy produced valve body and valve fitted with said valve body

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10000158.0 2000-01-06
DE10000158 2000-01-06

Publications (2)

Publication Number Publication Date
WO2001049979A2 true WO2001049979A2 (fr) 2001-07-12
WO2001049979A3 WO2001049979A3 (fr) 2002-02-28

Family

ID=7626758

Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/EP2001/000036 WO2001049979A2 (fr) 2000-01-06 2001-01-04 Corps de soupape produit par metallurgie des poudres et soupape equipee dudit corps de soupape
PCT/EP2001/000038 WO2001049436A2 (fr) 2000-01-06 2001-01-04 Piece moulee, frittee sous pression, produite par metallurgie des poudres

Family Applications After (1)

Application Number Title Priority Date Filing Date
PCT/EP2001/000038 WO2001049436A2 (fr) 2000-01-06 2001-01-04 Piece moulee, frittee sous pression, produite par metallurgie des poudres

Country Status (5)

Country Link
EP (1) EP1250518B1 (fr)
AT (1) ATE305084T1 (fr)
AU (2) AU3727401A (fr)
DE (2) DE10031960A1 (fr)
WO (2) WO2001049979A2 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102011109473A1 (de) 2011-08-04 2012-03-15 Daimler Ag Sinterbauteil und Nockenwelle
CN113564491A (zh) * 2021-07-02 2021-10-29 安徽森拓新材料有限公司 一种高性能粉末冶金气门导管材料

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2596067A1 (fr) * 1986-03-19 1987-09-25 Metafram Alliages Fritte Procede de fabrication de pieces en acier rapide fritte
US4964908A (en) * 1986-11-21 1990-10-23 Manganese Bronze Limited High density sintered ferrous alloys
US5656787A (en) * 1994-02-08 1997-08-12 Stackpole Limited Hi-density sintered alloy

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61270518A (ja) * 1985-05-22 1986-11-29 Toyota Motor Corp 焼結カムシヤフト
JPS62124256A (ja) * 1985-11-21 1987-06-05 Kawasaki Steel Corp 黒鉛が析出した摺動部材用焼結鋼

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2596067A1 (fr) * 1986-03-19 1987-09-25 Metafram Alliages Fritte Procede de fabrication de pieces en acier rapide fritte
US4964908A (en) * 1986-11-21 1990-10-23 Manganese Bronze Limited High density sintered ferrous alloys
US5656787A (en) * 1994-02-08 1997-08-12 Stackpole Limited Hi-density sintered alloy

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DATABASE CHEMABS [Online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; MURASE, HIROYUKI: "Wear resistant sintered camshafts" retrieved from STN Database accession no. 107:11319 CA XP002171319 & JP 61 270518 A (TOYOTA MOTOR CORP., JAPAN) 29. November 1986 (1986-11-29) *
DATABASE CHEMABS [Online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; NITSUTA, MINORU ET AL: "Graphite precipitated sintered steel for sliding parts" retrieved from STN Database accession no. 107:181148 CA XP002171321 & JP 62 124256 A (KAWASAKI STEEL CORP., JAPAN) 5. Juni 1987 (1987-06-05) *

Also Published As

Publication number Publication date
EP1250518A2 (fr) 2002-10-23
EP1250518B1 (fr) 2005-09-21
WO2001049436A2 (fr) 2001-07-12
AU2372001A (en) 2001-07-16
WO2001049979A3 (fr) 2002-02-28
AU3727401A (en) 2001-07-16
DE50107484D1 (de) 2005-10-27
WO2001049436A3 (fr) 2002-02-14
ATE305084T1 (de) 2005-10-15
DE10031960A1 (de) 2001-07-12

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