WO2020083808A1 - Gas exchange valve - Google Patents

Gas exchange valve Download PDF

Info

Publication number
WO2020083808A1
WO2020083808A1 PCT/EP2019/078492 EP2019078492W WO2020083808A1 WO 2020083808 A1 WO2020083808 A1 WO 2020083808A1 EP 2019078492 W EP2019078492 W EP 2019078492W WO 2020083808 A1 WO2020083808 A1 WO 2020083808A1
Authority
WO
WIPO (PCT)
Prior art keywords
nickel
phosphorus
boron carbide
gas exchange
valve
Prior art date
Application number
PCT/EP2019/078492
Other languages
German (de)
French (fr)
Inventor
Andreas Dogar
Stephan Körner
Christoph Luven
Alexander Müller
Original Assignee
Mahle 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 Mahle International Gmbh filed Critical Mahle International Gmbh
Priority to EP19795136.1A priority Critical patent/EP3870740A1/en
Publication of WO2020083808A1 publication Critical patent/WO2020083808A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D15/00—Electrolytic or electrophoretic production of coatings containing embedded materials, e.g. particles, whiskers, wires
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/10—Electroplating with more than one layer of the same or of different metals
    • C25D5/12—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium
    • C25D5/14—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium two or more layers being of nickel or chromium, e.g. duplex or triplex layers
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/60—Electroplating characterised by the structure or texture of the layers
    • C25D5/615—Microstructure of the layers, e.g. mixed structure
    • C25D5/617—Crystalline layers
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D7/00—Electroplating characterised by the article coated
    • 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
    • F01L3/04—Coated valve members or valve-seats
    • 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
    • F01L3/08—Valves guides; Sealing of valve stem, e.g. sealing by lubricant
    • 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
    • F01L2301/00—Using particular materials
    • F01L2301/02—Using ceramic materials
    • 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
    • F01L2820/00—Details on specific features characterising valve gear arrangements
    • F01L2820/01—Absolute values

Definitions

  • the invention relates to a gas exchange valve, a tribological system with such a gas exchange valve and an internal combustion engine with such a valve seat ring or such a tribological system.
  • the invention further relates to a method for coating a gas exchange valve.
  • a generic gas exchange valve of an internal combustion engine with a valve disk and a valve stem is known from DE 10 2014 225 741 A1.
  • a nickel-phosphorus layer is applied to the valve stem at least in some areas. In particular, this is intended to prevent excessive wear of the gas exchange valve during operation.
  • valve guide against which the valve stem rubs during operation of the internal combustion engine, is also subject to wear. This can result in the valve no longer returning centrally to the valve seat and not sealing well.
  • thermal and chemical loads such as those caused by oils, lubricants or other substances, also play a decisive role, since these can often have a negative impact on corrosion and thus wear resistance.
  • the present invention is therefore concerned with the problem of specifying an improved or at least an alternative embodiment for a gas exchange valve of the generic type, which is characterized in particular by increased wear resistance.
  • the present invention is based on the general idea of providing a gas exchange valve known per se with a valve disk and a valve stem, at least in some areas with an applied nickel-phosphorus-boron carbide layer.
  • a nickel-phosphorus-boron carbide layer has proven particularly good against wear of the gas exchange valve and the valve guide that guides the gas exchange valve during operation of the gas exchange valve.
  • a gas exchange valve comprises a valve stem and a valve disk, a nickel-phosphorus-boron carbide layer being arranged on the valve stem at least in regions.
  • the nickel-phosphorus-boron carbide layer contains 0.5 to 5% by weight, preferably 1.5 to 3% by weight, of phosphorus.
  • a phosphorus portion of the layer ensures a high wear resistance for the gas exchange valve and for a valve guide and a significantly increased corrosion protection for the gas exchange valve, which, in particular when used as an inlet or outlet valve, not only high thermal and mechanical, but also wet chemical corrosion (condensate corrosion ) is exposed.
  • the nickel-phosphorus-boron carbide layer contains 2 to 7% by weight, preferably 3 to 5% by weight, of boron carbide.
  • boron carbide portion of the layer also ensures a high wear resistance for the gas exchange valve and for the valve guide and a significantly increased corrosion protection for the gas exchange valve.
  • the nickel-phosphorus-boron carbide layer advantageously has a mixed hardness between 350 HV and 1500 HV, preferably between 400 HV and 800 HV. This embodiment proves to be particularly wear and corrosion resistant and reduces wear on the valve guide particularly well.
  • the nickel-phosphorus-boron carbide layer d has an average grain diameter of less than 5 ° 1, 5 miti, preferably less than 0.8 miti on. With such a particle diameter, the counterpart, i.e. the valve guide, is polished and not abrasively attacked.
  • the nickel-phosphorus-boron carbide layer has a layer thickness between 5 to 20 miti, preferably between 8 to 12 miti. In this way, wear on a particularly large surface of the valve stem and the valve guide is reduced on the one hand, and on the other hand, this embodiment enables the gas exchange valve to be manufactured particularly cost-effectively.
  • the nickel-phosphorus-boron carbide layer has a length between 60 mm and 140 mm along an axial direction of the valve stem. In this way, too, wear on a particularly large surface of the valve stem and the valve guide is reduced, and on the other hand, this embodiment enables the gas exchange valve to be manufactured particularly cost-effectively.
  • the nickel-phosphorus-boron carbide layer on the valve stem is expediently arranged exclusively in the region of a valve guide. This enables a particularly cost-efficient manufacture of the gas exchange valve.
  • the nickel-phosphorus-boron carbide layer on the valve stem is particularly expediently arranged all the way round. This embodiment also proves to be particularly resistant to wear and corrosion and reduces wear on the valve guide particularly well.
  • valve stem has a diameter between 5 mm and 10 mm.
  • the gas exchange valve contains the martensitic steels X45 and / or X85 and / or the austenitic steels X50 and / or nickel-based materials NCF 3015 and / or Nimonic80A.
  • Such a gas exchange valve proves to be particularly wear and corrosion resistant.
  • An adhesive layer with a layer thickness of less than 1 ⁇ m is particularly preferably arranged between the valve stem and the nickel-phosphorus-boron carbide layer. Such an adhesive layer enables an extremely firm connection of the nickel-phosphorus-boron carbide layer to the gas exchange valve.
  • the adhesive layer between the valve stem and the nickel-phosphorus-boron carbide layer likewise preferably contains nickel. Such an adhesive layer ensures a particularly strong connection of the nickel-phosphorus-boron carbide layer to the gas exchange valve.
  • the invention also relates to a tribological system which comprises a gas exchange valve and a valve guide which have been presented above.
  • a gas exchange valve and a valve guide which have been presented above.
  • the advantages of the gas exchange valve according to the invention explained above are thus also transferred to the tribological system according to the invention.
  • the invention further relates to an internal combustion engine for a motor vehicle.
  • the internal combustion engine comprises a previously described gas exchange valve which is a previously presented tribological system.
  • the above-explained advantages of the gas exchange valve according to the invention or of the tribological system according to the invention are therefore also transferred to the internal combustion engine according to the invention.
  • the invention further relates to a method for coating a gas exchange valve, which comprises a valve stem and a valve disk.
  • a nickel-phosphorus-boron carbide layer is applied galvanically to the valve stem at least in some areas.
  • the nickel-phosphorus-boron carbide layer is particularly advantageously applied galvanically by means of current densities between 30 A / dm 2 and 200 A / dm 2 , in particular between 90 A / dm 2 and 120 A / dm 2 .
  • This current density range enables an optimal proportion of nickel, phosphorus and boron carbide in the applied layer.
  • the applied nickel-phosphorus-boron carbide layer contains 0.5 to 5% by weight, preferably 1.5 to 3% by weight, of phosphorus.
  • a nickel portion of the applied layer ensures a high wear resistance for the gas exchange valve and for the valve guide and a significantly increased corrosion protection for the gas exchange valve.
  • the applied nickel-phosphorus-boron carbide layer contains 2 to 7% by weight, preferably 3 to 5% by weight, of boron carbide.
  • Such a proportion of boron carbide in the applied layer likewise ensures high wear resistance for the gas exchange valve and for the valve guide and significantly increased corrosion protection for the gas exchange valve.
  • An adhesive layer is particularly preferably applied galvanically between the valve stem and the nickel-phosphorus-boron carbide layer.
  • Such a detention Layer enables an extremely firm connection of the nickel-phosphorus-boron carbide layer with the gas exchange valve.
  • the adhesive layer between the valve stem and the nickel-phosphorus-boron carbide layer is also advantageously applied galvanically by means of current densities between 4 A / dm 2 and 40 A / dm 2 , in particular between 25 A / dm 2 and 35 A / dm 2 - brought.
  • This current density range enables a particularly firm connection of the adhesive layer to the gas exchange valve and a particularly firm connection of the nickel-phosphorus-boron carbide layer to the gas exchange valve by means of the adhesive layer.
  • the applied adhesive layer between the valve stem and the nickel-phosphorus-boron carbide layer likewise preferably contains nickel. Such an applied adhesive layer ensures a particularly firm connection of the nickel-phosphorus-boron carbide layer to the gas exchange valve.
  • FIG. 1 illustrates an example of a gas exchange valve 1 according to the invention of an internal combustion engine, which is otherwise not shown and which has a valve. Includes tilteller 2 and a valve stem 3.
  • the gas exchange valve 1 is usually designed as an inlet or outlet valve.
  • a nickel-phosphorus-boron carbide layer 4 (see also the detailed illustration in FIG. 1) is arranged on the valve stem 3 at least in regions. This can, for example, be applied galvanically using current densities between 30 A / dm 2 and 200 A / dm 2 , in particular between 90 A / dm 2 and 120 A / dm 2 .
  • the nickel-phosphorus-boron carbide layer 4 contains 0.5 to 5% by weight of phosphorus. It preferably contains 1.5 to 3% by weight of phosphorus.
  • the nickel-phosphorus-boron carbide layer 4 also contains 2 to 7% by weight of boron carbide. It preferably contains 3 to 5% by weight boron carbide.
  • the nickel-phosphorus-boron carbide layer 4 has a mixing hardness between 350 HV and 1500 HV or preferably between 400 HV and 800 HV and a mean grain diameter d 5 o of less than 1, 5 miti, preferably from 0.8 miti on .
  • the nickel-phosphorus-boron carbide layer 4 has a layer thickness dnp between 5 to 20 miti, preferably between 8 to 12 miti, and a length along an axial direction A of the valve stem 3 between 60 mm and 140 mm.
  • the nickel-phosphorus-boron carbide layer 4 is arranged on the valve stem 3 exclusively in the region 6 of a valve guide, not shown in FIG. 1, and is also arranged on the valve stem 3 in a completely circumferential manner.
  • the valve stem 3 has a diameter between 5 mm and 10 mm and the gas exchange valve 1 contains the martensitic steels X45 and, alternatively or additionally, X85 and / or the austenitic steels X50 and, alternatively or additionally, nickel-based materials NCF 3015 and, alternatively or in addition, Nimonic80A.
  • An adhesive layer 5 with a layer thickness of less than 1 mm is arranged between the valve stem 3 and the nickel-phosphorus-boron carbide layer 4.
  • the adhesive layer 5 between the valve stem 3 and the nickel-phosphorus-boron carbide layer 4 contains nickel.
  • the adhesive layer can be applied in the area 6 of a valve guide of the valve stem 3 and by means of current densities between 4 A / dm 2 and 40 A / dm 2 , in particular between 25 A / dm 2 and 35 A / dm 2 .
  • the nickel-phosphorus-boron carbide layer 4 is galvanically coated on the valve stem 3 at least in regions by means of current densities between 30 A / dm 2 and 200 A / dm 2 , in particular between 90 A / dm 2 and 120 A / dm 2 , applied.
  • the applied nickel-phosphorus-boron carbide layer 4 contains 0.5 to 5% by weight, preferably 1.5 to 3% by weight, phosphorus and 2 to 7% by weight, preferably 3 to 5% by weight. %, Boron carbide.
  • An adhesive layer 5 is previously applied galvanically between the valve stem 3 and the nickel-phosphorus-boron carbide layer 4 by means of current densities between 4 A / dm 2 and 40 A / dm 2 , in particular between 25 A / dm 2 and 35 A / dm 2 .
  • the applied adhesive layer 5 contains nickel.
  • the nickel-phosphorus-boron carbide layer 4 can be applied by means of an electroplating bath (not shown in FIG. 1) using an electroplating liquid and an anode arranged therein.
  • the anode has a receptacle in which the gas exchange valve 1 to be coated is received with one end of the valve stem 3.
  • An extremely homogeneous and uniform layer thickness distribution can be achieved by using a shaped anode.
  • a cathode via which current can be introduced into gas exchange valve 1 by means of a current source.
  • the gas exchange til 1 the actual cathode through which current flows to the anode.
  • a mixing device can also be provided, by means of which the electroplating liquid is mixed well during the electroplating, so that an always sufficiently high proportion of phosphorus and, alternatively or additionally, boron carbide and, alternatively or additionally, nickel for producing the nickel-phosphorus - Boron carbide layer 4 can reach the surface of the valve stem 3. In addition, this also prevents an undesired deposition of hydrogen, which would hinder the deposition of phosphorus.
  • the anode is usually a so-called mixed metal oxide (MMO) anode.
  • MMO mixed metal oxide

Abstract

The invention relates to a gas exchange valve (1) comprising a valve stem (3) and a valve disk (2). A nickel-phosphorus-boron carbide layer (4) is disposed in at least some areas on the valve stem (3) of the gas exchange valve (1).

Description

Gaswechselventil  Gas exchange valve
Die Erfindung betrifft ein Gaswechselventil, ein tribologisches System mit einem- solchen Gaswechselventil und eine Brennkraftmaschine mit einem solchen Ventil sitzring oder einem solchen tribologischen System. Die Erfindung betrifft ferner ein Verfahren zum Beschichten eines Gaswechselventils. The invention relates to a gas exchange valve, a tribological system with such a gas exchange valve and an internal combustion engine with such a valve seat ring or such a tribological system. The invention further relates to a method for coating a gas exchange valve.
Aus der DE 10 2014 225 741 A1 ist ein gattungsgemäßes Gaswechselventil einer Brennkraftmaschine mit einem Ventilteller und einem Ventilschaft bekannt. Hierbei ist am Ventilschaft zumindest bereichsweise eine Nickel-Phosphor-Schicht aufge- bracht. Hierdurch soll insbesondere ein übermäßiger Verschleiß des Gaswechsel- ventils im Betrieb verhindert werden. A generic gas exchange valve of an internal combustion engine with a valve disk and a valve stem is known from DE 10 2014 225 741 A1. A nickel-phosphorus layer is applied to the valve stem at least in some areas. In particular, this is intended to prevent excessive wear of the gas exchange valve during operation.
Generell sind Gaswechselventile in Brennkraftmaschinen hohen thermischen und/oder mechanischen Belastungen ausgesetzt. Auch die Ventilführung, an wel- cher der Ventilschaft während des Betriebs der Brennkraftmaschine reibt, ist ei- nem Verschleiß ausgesetzt. Die kann dazu führen, dass das Ventil nicht mehr zentrisch auf den Ventilsitz zurückkehrt und nicht gut abdichtet. Neben mechani- schen Belastungen spielen auch thermische und chemische Belastungen, bei- spielsweise durch Öle, Schmiermittel oder andere Stoffe, eine entscheidende Rol- le, da sich diese oftmals negativ auf die Korrosions- und damit die Verschleißbe- ständigkeit auswirken können. Generally, gas exchange valves in internal combustion engines are exposed to high thermal and / or mechanical loads. The valve guide, against which the valve stem rubs during operation of the internal combustion engine, is also subject to wear. This can result in the valve no longer returning centrally to the valve seat and not sealing well. In addition to mechanical loads, thermal and chemical loads, such as those caused by oils, lubricants or other substances, also play a decisive role, since these can often have a negative impact on corrosion and thus wear resistance.
Die vorliegende Erfindung beschäftigt sich daher mit dem Problem, für ein Gas- wechselventil der gattungsgemäßen Art eine verbesserte oder zumindest eine al- ternative Ausführungsform anzugeben, welche sich insbesondere durch eine er höhte Verschleißbeständigkeit auszeichnet. The present invention is therefore concerned with the problem of specifying an improved or at least an alternative embodiment for a gas exchange valve of the generic type, which is characterized in particular by increased wear resistance.
Dieses Problem wird erfindungsgemäß durch den Gegenstand des unabhängigen Anspruchs 1 gelöst. Vorteilhafte Au sfü h ru ng sform en sind Gegenstand der abhän- gigen Ansprüche. This problem is solved according to the invention by the subject of independent Claim 1 solved. Advantageous designs are the subject of the dependent claims.
Die vorliegende Erfindung beruht auf dem allgemeinen Gedanken, ein an sich be- kanntes Gaswechselventil mit einem Ventilteller und einem Ventilschaft, zumin- dest am Ventilschaft zumindest bereichsweise mit einer aufgebrachten Nickel- Phosphor-Borcarbid Schicht zu versehen. Eine derartig ausgebildete Nickel- Phosphor-Borcarbid Schicht hat sich besonders gut gegenüber einem Verschleiß des Gaswechselventils und der Ventilführung, welche das Gaswechselventil im Betrieb des Gaswechselventils führt, erwiesen. The present invention is based on the general idea of providing a gas exchange valve known per se with a valve disk and a valve stem, at least in some areas with an applied nickel-phosphorus-boron carbide layer. Such a nickel-phosphorus-boron carbide layer has proven particularly good against wear of the gas exchange valve and the valve guide that guides the gas exchange valve during operation of the gas exchange valve.
Diese Aufgabe wird erfindungsgemäß durch den Gegenstand der unabhängigen Patentansprüche gelöst. Vorteilhafte Ausführungsformen sind Gegenstand der abhängigen Patentansprüche. This object is achieved according to the invention by the subject matter of the independent claims. Advantageous embodiments are the subject of the dependent claims.
Ein erfindungsgemäßes Gaswechselventil umfasst einen Ventilschaft und einen Ventilteller, wobei auf dem Ventilschaft zumindest bereichsweise eine Nickel- Phosphor-Borcarbid-Schicht angeordnet ist. A gas exchange valve according to the invention comprises a valve stem and a valve disk, a nickel-phosphorus-boron carbide layer being arranged on the valve stem at least in regions.
Gemäß einer bevorzugten Ausführungsform enthält die Nickel-Phosphor- Borcarbid-Schicht 0,5 bis 5 Gew.-%, vorzugsweise 1 ,5 bis 3 Gew.-%, Phosphor. Ein derartiger Phosphoranteil der Schicht gewährleistet eine hohe Verschleißbe- ständigkeit für das Gaswechselventil und für eine Ventilführung und einen deutlich erhöhten Korrosionsschutz für das Gaswechselventil, welches insbesondere bei einem Einsatz als Einlass- oder Auslassventil nicht nur hohen thermischen und mechanischen, sondern auch nasschemischer Korrosion (Kondensatkorrosion) ausgesetzt ist. According to a preferred embodiment, the nickel-phosphorus-boron carbide layer contains 0.5 to 5% by weight, preferably 1.5 to 3% by weight, of phosphorus. Such a phosphorus portion of the layer ensures a high wear resistance for the gas exchange valve and for a valve guide and a significantly increased corrosion protection for the gas exchange valve, which, in particular when used as an inlet or outlet valve, not only high thermal and mechanical, but also wet chemical corrosion (condensate corrosion ) is exposed.
Gemäß einer weiteren bevorzugten Ausführungsform enthält die Nickel-Phosphor- Borcarbid-Schicht 2 bis 7 Gew.-%, vorzugsweise 3 bis 5 Gew.-%, Borcarbid. Ein derartiger Borcarbidanteil der Schicht gewährleistet ebenfalls eine hohe Ver- schleißbeständigkeit für das Gaswechselventil und für die Ventilführung und einen deutlich erhöhten Korrosionsschutz für das Gaswechselventil. According to a further preferred embodiment, the nickel-phosphorus-boron carbide layer contains 2 to 7% by weight, preferably 3 to 5% by weight, of boron carbide. Such a boron carbide portion of the layer also ensures a high wear resistance for the gas exchange valve and for the valve guide and a significantly increased corrosion protection for the gas exchange valve.
Vorteilhaft weist die Nickel-Phosphor-Borcarbid-Schicht eine Mischhärte zwischen 350 HV und 1500 HV, vorzugsweise zwischen 400 HV und 800 HV, auf. Diese Ausführungsform erweist sich als besonders Verschleiß- und Korrosionsbeständig und reduziert den Verschleiß an der Ventilführung besonders gut. The nickel-phosphorus-boron carbide layer advantageously has a mixed hardness between 350 HV and 1500 HV, preferably between 400 HV and 800 HV. This embodiment proves to be particularly wear and corrosion resistant and reduces wear on the valve guide particularly well.
Besonders vorteilhaft weist die Nickel-Phosphor-Borcarbid-Schicht einen mittleren Korndurchmesser d5o von weniger als 1 ,5 miti, vorzugsweise weniger als 0,8 miti, auf. Bei einem solchen Partikeldurchmesser wird der Gegenlaufpartner, also die Ventilführung, poliert und nicht abrasiv angegriffen. Particularly advantageously, the nickel-phosphorus-boron carbide layer d has an average grain diameter of less than 5 ° 1, 5 miti, preferably less than 0.8 miti on. With such a particle diameter, the counterpart, i.e. the valve guide, is polished and not abrasively attacked.
Gemäß einer vorteilhaften Ausführungsform weist die Nickel-Phosphor-Borcarbid- Schicht eine Schichtdicke zwischen 5 bis 20 miti, vorzugweise zwischen 8 bis 12 miti, auf. Auf diese Weise wird einerseits Verschleiß an einer besonders großen Oberfläche des Ventilschafts und der Ventilführung reduziert und andererseits er- möglicht diese Ausführungsform eine besonders kostengünstige Herstellung des Gaswechselventils. According to an advantageous embodiment, the nickel-phosphorus-boron carbide layer has a layer thickness between 5 to 20 miti, preferably between 8 to 12 miti. In this way, wear on a particularly large surface of the valve stem and the valve guide is reduced on the one hand, and on the other hand, this embodiment enables the gas exchange valve to be manufactured particularly cost-effectively.
Gemäß einer weiteren vorteilhaften Ausführungsform weist die Nickel-Phosphor- Borcarbid-Schicht entlang einer axialen Richtung des Ventilschafts eine Länge zwischen 60 mm und 140 mm auf. Auch auf diese Weise wird einerseits Ver- schleiß an einer besonders großen Oberfläche des Ventilschafts und der Ventil führung reduziert und andererseits ermöglicht diese Ausführungsform eine beson- ders kostengünstige Herstellung des Gaswechselventils. According to a further advantageous embodiment, the nickel-phosphorus-boron carbide layer has a length between 60 mm and 140 mm along an axial direction of the valve stem. In this way, too, wear on a particularly large surface of the valve stem and the valve guide is reduced, and on the other hand, this embodiment enables the gas exchange valve to be manufactured particularly cost-effectively.
Zweckmäßig ist die Nickel-Phosphor-Borcarbid-Schicht auf dem Ventilschaft aus- schließlich im Bereich einer Ventilführung angeordnet. Dies ermöglicht eine be- sonders kosteneffiziente Herstellung des Gaswechselventils. Besonders zweckmäßig ist die Nickel-Phosphor-Borcarbid-Schicht auf dem Ventil schaft vollständig umlaufend angeordnet. Auch diese Ausführungsform erweist sich als besonders Verschleiß- und Korrosionsbeständig und reduziert den Ver- schleiß an der Ventilführung besonders gut. The nickel-phosphorus-boron carbide layer on the valve stem is expediently arranged exclusively in the region of a valve guide. This enables a particularly cost-efficient manufacture of the gas exchange valve. The nickel-phosphorus-boron carbide layer on the valve stem is particularly expediently arranged all the way round. This embodiment also proves to be particularly resistant to wear and corrosion and reduces wear on the valve guide particularly well.
Gemäß einer weiteren vorteilhaften Ausführungsform weist der Ventilschaft einen Durchmesser zwischen 5 mm und 10 mm auf. According to a further advantageous embodiment, the valve stem has a diameter between 5 mm and 10 mm.
Gemäß einer ebenfalls vorteilhaften Ausführungsform enthält das Gaswechselven- til die martensitischen Stähle X45 und/oder X85 und/oder die austenitischen Stäh- le X50 und/oder Nickelbasiswerkstoffe NCF 3015 und/oder Nimonic80A. Ein der- artiges Gaswechselventil erweist sich als besonders verschleiß- und korrosions- beständig. According to a likewise advantageous embodiment, the gas exchange valve contains the martensitic steels X45 and / or X85 and / or the austenitic steels X50 and / or nickel-based materials NCF 3015 and / or Nimonic80A. Such a gas exchange valve proves to be particularly wear and corrosion resistant.
Besonders bevorzugt ist zwischen dem Ventilschaft und der Nickel-Phosphor- Borcarbid-Schicht eine Haftschicht mit einer Schichtdicke von weniger als 1 pm angeordnet. Eine solche Haftschicht ermöglicht eine äußerst feste Verbindung der Nickel-Phosphor-Borcarbid Schicht mit dem Gaswechselventil. An adhesive layer with a layer thickness of less than 1 μm is particularly preferably arranged between the valve stem and the nickel-phosphorus-boron carbide layer. Such an adhesive layer enables an extremely firm connection of the nickel-phosphorus-boron carbide layer to the gas exchange valve.
Ebenfalls bevorzugt enthält die Haftschicht zwischen dem Ventilschaft und der Nickel-Phosphor-Borcarbid-Schicht Nickel. Eine derartige Haftschicht gewährleis- tet eine besonders feste Verbindung der Nickel-Phosphor-Borcarbid Schicht mit dem Gaswechselventil. The adhesive layer between the valve stem and the nickel-phosphorus-boron carbide layer likewise preferably contains nickel. Such an adhesive layer ensures a particularly strong connection of the nickel-phosphorus-boron carbide layer to the gas exchange valve.
Die Erfindung betrifft auch ein tribologisches System, welches ein vorangehend vorgestelltes Gaswechselventil und eine Ventilführung umfasst. Die vorangehend erläuterten Vorteile des erfindungsgemäßen Gaswechselventils übertragen sich somit auch auf das erfindungsgemäße tribologische System. The invention also relates to a tribological system which comprises a gas exchange valve and a valve guide which have been presented above. The advantages of the gas exchange valve according to the invention explained above are thus also transferred to the tribological system according to the invention.
Die Erfindung betrifft ferner eine Brennkraftmaschine für ein Kraftfahrzeug. Die Brennkraftmaschine umfasst ein vorangehend vorgestelltes Gaswechselventil o- der ein vorangehend vorgestelltes tribologisches System. Die vorangehend erläu- terten Vorteile des erfindungsgemäßen Gaswechselventils beziehungsweise des erfindungsgemäßen tribologischen Systems übertragen sich daher auch auf die erfindungsgemäße Brennkraftmaschine. The invention further relates to an internal combustion engine for a motor vehicle. The internal combustion engine comprises a previously described gas exchange valve which is a previously presented tribological system. The above-explained advantages of the gas exchange valve according to the invention or of the tribological system according to the invention are therefore also transferred to the internal combustion engine according to the invention.
Noch ferner betrifft die Erfindung ein Verfahren zum Beschichten eines Gaswech- selventils, welches einen Ventilschaft und einen Ventilteller umfasst. Gemäß dem erfindungsgemäßen Verfahren wird auf dem Ventilschaft zumindest bereichsweise eine Nickel-Phosphor-Borcarbid-Schicht galvanisch aufgebracht. The invention further relates to a method for coating a gas exchange valve, which comprises a valve stem and a valve disk. According to the method according to the invention, a nickel-phosphorus-boron carbide layer is applied galvanically to the valve stem at least in some areas.
Besonders vorteilhaft wird die Nickel-Phosphor-Borcarbid-Schicht galvanisch mit- tels Stromdichten zwischen 30 A/dm2 und 200 A/dm2, insbesondere zwischen 90 A/dm2 und 120 A/dm2, aufgebracht. Dieser Stromdichtebereich ermöglicht einen optimalen Anteil an Nickel, Phosphor und Borcarbid in der aufgebrachten Schicht. The nickel-phosphorus-boron carbide layer is particularly advantageously applied galvanically by means of current densities between 30 A / dm 2 and 200 A / dm 2 , in particular between 90 A / dm 2 and 120 A / dm 2 . This current density range enables an optimal proportion of nickel, phosphorus and boron carbide in the applied layer.
Gemäß einer bevorzugten Ausführungsform enthält die aufgebrachte Nickel- Phosphor-Borcarbid-Schicht 0,5 bis 5 Gew.-%, vorzugsweise 1 ,5 bis 3 Gew.-%, Phosphor. Ein derartiger Nickelanteil der aufgebrachten Schicht gewährleistet eine hohe Verschleißbeständigkeit für das Gaswechselventil und für die Ventilführung und einen deutlich erhöhten Korrosionsschutz für das Gaswechselventil. According to a preferred embodiment, the applied nickel-phosphorus-boron carbide layer contains 0.5 to 5% by weight, preferably 1.5 to 3% by weight, of phosphorus. Such a nickel portion of the applied layer ensures a high wear resistance for the gas exchange valve and for the valve guide and a significantly increased corrosion protection for the gas exchange valve.
Gemäß einer weiteren bevorzugten Ausführungsform enthält die aufgebrachte Nickel-Phosphor-Borcarbid-Schicht 2 bis 7 Gew.-%, vorzugsweise 3 bis 5 Gew.-%, Borcarbid. Ein derartiger Borcarbidanteil der aufgebrachten Schicht gewährleistet ebenfalls eine hohe Verschleißbeständigkeit für das Gaswechselventil und für die Ventilführung und einen deutlich erhöhten Korrosionsschutz für das Gaswechsel- ventil. According to a further preferred embodiment, the applied nickel-phosphorus-boron carbide layer contains 2 to 7% by weight, preferably 3 to 5% by weight, of boron carbide. Such a proportion of boron carbide in the applied layer likewise ensures high wear resistance for the gas exchange valve and for the valve guide and significantly increased corrosion protection for the gas exchange valve.
Besonders bevorzugt ist zwischen dem Ventilschaft und der Nickel-Phosphor- Borcarbid-Schicht eine Haftschicht galvanisch aufgebracht. Eine solche Haft- Schicht ermöglicht eine äußerst feste Verbindung der Nickel-Phosphor-Borcarbid Schicht mit dem Gaswechselventil. An adhesive layer is particularly preferably applied galvanically between the valve stem and the nickel-phosphorus-boron carbide layer. Such a detention Layer enables an extremely firm connection of the nickel-phosphorus-boron carbide layer with the gas exchange valve.
Ebenfalls vorteilhaft wird die Haftschicht zwischen dem Ventilschaft und der Ni- ckel-Phosphor-Borcarbid-Schicht galvanisch mittels Stromdichten zwischen 4 A/dm2 und 40 A/dm2, insbesondere zwischen 25 A/dm2 und 35 A/dm2, aufge- bracht. Dieser Stromdichtebereich ermöglicht eine besonders feste Verbindung der Haftschicht mit dem Gaswechselventil und eine besonders feste Verbindung der Nickel-Phosphor-Borcarbid Schicht mit dem Gaswechselventil mittels der Haftschicht. The adhesive layer between the valve stem and the nickel-phosphorus-boron carbide layer is also advantageously applied galvanically by means of current densities between 4 A / dm 2 and 40 A / dm 2 , in particular between 25 A / dm 2 and 35 A / dm 2 - brought. This current density range enables a particularly firm connection of the adhesive layer to the gas exchange valve and a particularly firm connection of the nickel-phosphorus-boron carbide layer to the gas exchange valve by means of the adhesive layer.
Ebenfalls bevorzugt enthält die aufgebrachte Haftschicht zwischen dem Ventil- schaft und der Nickel-Phosphor-Borcarbid-Schicht Nickel. Eine derartige aufge- brachte Haftschicht gewährleistet eine besonders feste Verbindung der Nickel- Phosphor-Borcarbid Schicht mit dem Gaswechselventil. The applied adhesive layer between the valve stem and the nickel-phosphorus-boron carbide layer likewise preferably contains nickel. Such an applied adhesive layer ensures a particularly firm connection of the nickel-phosphorus-boron carbide layer to the gas exchange valve.
Weitere wichtige Merkmale und Vorteile der Erfindung ergeben sich aus den Un- teransprüchen, aus der Zeichnung und aus der zugehörigen Figurenbeschreibung anhand der Zeichnung. Further important features and advantages of the invention result from the subclaims, from the drawing and from the associated description of the figures on the basis of the drawing.
Es versteht sich, dass die vorstehend genannten und die nachstehend noch zu erläuternden Merkmale nicht nur in der jeweils angegebenen Kombination, son- dern auch in anderen Kombinationen oder in Alleinstellung verwendbar sind, ohne den Rahmen der vorliegenden Erfindung zu verlassen. It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.
Ein bevorzugtes Ausführungsbeispiel der Erfindung ist in der Figur dargestellt und wird in der nachfolgenden Beschreibung näher erläutert. A preferred embodiment of the invention is shown in the figure and is explained in more detail in the following description.
Die einzige Figur 1 illustriert ein Beispiel eines erfindungsgemäßen Gaswechsel- ventils 1 einer im Übrigen nicht gezeigten Brennkraftmaschine, welche einen Ven- tilteller 2 sowie einen Ventilschaft 3 umfasst. Das Gaswechselventil 1 ist dabei üblicherweise als Einlass- oder Auslassventil ausgebildet. The only FIG. 1 illustrates an example of a gas exchange valve 1 according to the invention of an internal combustion engine, which is otherwise not shown and which has a valve. Includes tilteller 2 and a valve stem 3. The gas exchange valve 1 is usually designed as an inlet or outlet valve.
Auf dem Ventilschaft 3 ist zumindest bereichsweise eine Nickel-Phosphor- Borcarbid-Schicht 4 (vgl. auch die Detaildarstellung in Fig. 1 ) angeordnet. Diese kann beispielsweise galvanisch unter Verwendung von Stromdichten zwischen 30 A/dm2 und 200 A/dm2, insbesondere zwischen 90 A/dm2 und 120 A/dm2, aufge- bracht sein. A nickel-phosphorus-boron carbide layer 4 (see also the detailed illustration in FIG. 1) is arranged on the valve stem 3 at least in regions. This can, for example, be applied galvanically using current densities between 30 A / dm 2 and 200 A / dm 2 , in particular between 90 A / dm 2 and 120 A / dm 2 .
Die Nickel-Phosphor-Borcarbid-Schicht 4 enthält 0,5 bis 5 Gew.-% Phosphor. Vor- zugsweise enthält sie 1 ,5 bis 3 Gew.-% Phosphor. Die Nickel-Phosphor-Borcarbid- Schicht 4 enthält zudem 2 bis 7 Gew.-% Borcarbid. Vorzugsweise enthält sie 3 bis 5 Gew.-% Borcarbid. Die Nickel-Phosphor-Borcarbid-Schicht 4 weist dabei eine Mischhärte zwischen 350 HV und 1500 HV oder vorzugsweise zwischen 400 HV und 800 HV und einen mittleren Korndurchmesser d5o von weniger als 1 ,5 miti, vorzugsweise von 0,8 miti, auf. The nickel-phosphorus-boron carbide layer 4 contains 0.5 to 5% by weight of phosphorus. It preferably contains 1.5 to 3% by weight of phosphorus. The nickel-phosphorus-boron carbide layer 4 also contains 2 to 7% by weight of boron carbide. It preferably contains 3 to 5% by weight boron carbide. The nickel-phosphorus-boron carbide layer 4 has a mixing hardness between 350 HV and 1500 HV or preferably between 400 HV and 800 HV and a mean grain diameter d 5 o of less than 1, 5 miti, preferably from 0.8 miti on .
Außerdem weist die Nickel-Phosphor-Borcarbid-Schicht 4 eine Schichtdicke dnp zwischen 5 bis 20 miti, vorzugweise zwischen 8 bis 12 miti, und eine Länge entlang einer axialen Richtung A des Ventilschafts 3 zwischen 60 mm und 140 mm auf.In addition, the nickel-phosphorus-boron carbide layer 4 has a layer thickness dnp between 5 to 20 miti, preferably between 8 to 12 miti, and a length along an axial direction A of the valve stem 3 between 60 mm and 140 mm.
Die Nickel-Phosphor-Borcarbid-Schicht 4 ist auf dem Ventilschaft 3 ausschließlich im Bereich 6 einer nicht in Figur 1 gezeigten Ventilführung angeordnet und ist au- ßerdem auf dem Ventilschaft 3 vollständig umlaufend angeordnet. The nickel-phosphorus-boron carbide layer 4 is arranged on the valve stem 3 exclusively in the region 6 of a valve guide, not shown in FIG. 1, and is also arranged on the valve stem 3 in a completely circumferential manner.
Der Ventilschaft 3 weist einen Durchmesser zwischen 5 mm und 10 mm auf und das Gaswechselventil 1 enthält die martensitischen Stähle X45 und, alternativ o- der zusätzlich, X85 und/oder die austenitischen Stähle X50 und, alternativ oder zusätzlich, Nickelbasiswerkstoffe NCF 3015 und, alternativ oder zusätzlich, Nimo- nic80A. Zwischen dem Ventilschaft 3 und der Nickel-Phosphor-Borcarbid-Schicht 4 ist eine Haftschicht 5 mit einer Schichtdicke von weniger als 1 miti angeordnet. Die Haft- schicht 5 zwischen dem Ventilschaft 3 und der Nickel-Phosphor-Borcarbid-Schicht 4 enthält dabei Nickel. Die Haftschicht kann dabei im Bereich 6 einer Ventilführung des Ventilschaftes 3 und mittels Stromdichten zwischen 4 A/dm2 und 40 A/dm2, insbesondere zwischen 25 A/dm2 und 35 A/dm2, aufgebracht sein. The valve stem 3 has a diameter between 5 mm and 10 mm and the gas exchange valve 1 contains the martensitic steels X45 and, alternatively or additionally, X85 and / or the austenitic steels X50 and, alternatively or additionally, nickel-based materials NCF 3015 and, alternatively or in addition, Nimonic80A. An adhesive layer 5 with a layer thickness of less than 1 mm is arranged between the valve stem 3 and the nickel-phosphorus-boron carbide layer 4. The adhesive layer 5 between the valve stem 3 and the nickel-phosphorus-boron carbide layer 4 contains nickel. The adhesive layer can be applied in the area 6 of a valve guide of the valve stem 3 and by means of current densities between 4 A / dm 2 and 40 A / dm 2 , in particular between 25 A / dm 2 and 35 A / dm 2 .
Im Folgenden wird anhand der Figur 1 das erfindungsgemäße Verfahren zum Be- schichten des Gaswechselventils beispielhaft erläutert: The method according to the invention for coating the gas exchange valve is explained by way of example below with reference to FIG. 1:
Gemäß dem Verfahren zum Beschichten des Gaswechselventils 1 , welches den Ventilschaft 3 und den Ventilteller 2 umfasst, wir auf dem Ventilschaft 3 zumindest bereichsweise die Nickel-Phosphor-Borcarbid-Schicht 4 galvanisch mittels Strom- dichten zwischen 30 A/dm2 und 200 A/dm2, insbesondere zwischen 90 A/dm2 und 120 A/dm2, aufgebracht. Die aufgebrachte Nickel-Phosphor-Borcarbid-Schicht 4 enthält dabei 0,5 bis 5 Gew.-%, vorzugsweise 1 ,5 bis 3 Gew.-%, Phosphor und 2 bis 7 Gew.-%, vorzugsweise 3 bis 5 Gew.-%, Borcarbid. According to the method for coating the gas exchange valve 1, which comprises the valve stem 3 and the valve disk 2, the nickel-phosphorus-boron carbide layer 4 is galvanically coated on the valve stem 3 at least in regions by means of current densities between 30 A / dm 2 and 200 A / dm 2 , in particular between 90 A / dm 2 and 120 A / dm 2 , applied. The applied nickel-phosphorus-boron carbide layer 4 contains 0.5 to 5% by weight, preferably 1.5 to 3% by weight, phosphorus and 2 to 7% by weight, preferably 3 to 5% by weight. %, Boron carbide.
Zuvor wird zwischen dem Ventilschaft 3 und der Nickel-Phosphor-Borcarbid- Schicht 4 eine Haftschicht 5 galvanisch mittels Stromdichten zwischen 4 A/dm2 und 40 A/dm2, insbesondere zwischen 25 A/dm2 und 35 A/dm2, aufgebracht. Die aufgebrachte Haftschicht 5 enthält dabei Nickel. An adhesive layer 5 is previously applied galvanically between the valve stem 3 and the nickel-phosphorus-boron carbide layer 4 by means of current densities between 4 A / dm 2 and 40 A / dm 2 , in particular between 25 A / dm 2 and 35 A / dm 2 . The applied adhesive layer 5 contains nickel.
Das Aufbringen der Nickel-Phosphor-Borcarbid-Schicht 4 mittels eines Galvanik- bads (nicht in Figur 1 gezeigt) kann mit einer Galvanikflüssigkeit und mit einer da- rin angeordneten Anode erfolgen. Die Anode besitzt eine Aufnahme, in welcher das zu beschichtende Gaswechselventil 1 mit einem Ende des Ventilschafts 3 aufgenommen ist. Durch die Verwendung einer Formanode kann dabei eine äu- ßerst homogene und gleichmäßige Schichtdickenverteilung erreicht werden. The nickel-phosphorus-boron carbide layer 4 can be applied by means of an electroplating bath (not shown in FIG. 1) using an electroplating liquid and an anode arranged therein. The anode has a receptacle in which the gas exchange valve 1 to be coated is received with one end of the valve stem 3. An extremely homogeneous and uniform layer thickness distribution can be achieved by using a shaped anode.
Ebenfalls vorgesehen ist eine Kathode über die Strom mittels einer Stromquelle in das Gaswechselventil 1 einleitbar ist. In diesem Fall ist somit das Gaswechselven- til 1 die eigentliche Kathode, über welche Strom zur Anode fließt. Ebenfalls vorge- sehen sein kann eine Mischeinrichtung, mittels welcher die Galvanikflüssigkeit während des galvanischen Beschichtens gut durchmischt wird, so dass ein stets ausreichend hoher Anteil an Phosphor und, alternativ oder zusätzlich, Borcarbid und, alternativ oder zusätzlich, Nickel zum Herstellen der Nickel-Phosphor- Borcarbid-Schicht 4 an die Oberfläche des Ventilschaftes 3 gelangen kann. Zu- sätzlich wird hierdurch auch eine unerwünschte Ablagerung von Wasserstoff ver- hindert, welche die Abscheidung von Phosphor behindern würde. Die Anode ist dabei in der Regel eine sog. Mixed Metal Oxide (MMO) Anode. Selbstverständlich ist es denkbar, dass nicht nur der Ventilschaft 3, sondern zusätzlich zumindest die Ventilkehle mit der erfindungsgemäßen Nickel-Phosphor-Borcarbid-Schicht 4 zur verbesserten Verschleiß- und Korrosionsbeständigkeit überzogen ist. Also provided is a cathode via which current can be introduced into gas exchange valve 1 by means of a current source. In this case, the gas exchange til 1 the actual cathode through which current flows to the anode. A mixing device can also be provided, by means of which the electroplating liquid is mixed well during the electroplating, so that an always sufficiently high proportion of phosphorus and, alternatively or additionally, boron carbide and, alternatively or additionally, nickel for producing the nickel-phosphorus - Boron carbide layer 4 can reach the surface of the valve stem 3. In addition, this also prevents an undesired deposition of hydrogen, which would hinder the deposition of phosphorus. The anode is usually a so-called mixed metal oxide (MMO) anode. Of course, it is conceivable that not only the valve stem 3, but also at least the valve throat is coated with the nickel-phosphorus-boron carbide layer 4 according to the invention for improved wear and corrosion resistance.
**********

Claims

Ansprüche Expectations
1. Gaswechselventil (1 ), umfassend einen Ventilschaft (3) und einen Ventilteller1. Gas exchange valve (1), comprising a valve stem (3) and a valve plate
(2), (2),
wobei auf dem Ventilschaft (3) zumindest bereichsweise eine Nickel-Phosphor- Borcarbid-Schicht (4) angeordnet ist. a nickel-phosphorus-boron carbide layer (4) being arranged on the valve stem (3) at least in some areas.
2. Gaswechselventil nach Anspruch 1 , 2. Gas exchange valve according to claim 1,
dadurch gekennzeichnet, dass characterized in that
die Nickel-Phosphor-Borcarbid-Schicht (4) 0,5 bis 5 Gew.-%, vorzugsweise 1 ,5 bis 3 Gew.-%, Phosphor enthält. the nickel-phosphorus-boron carbide layer (4) contains 0.5 to 5% by weight, preferably 1.5 to 3% by weight, of phosphorus.
3. Gaswechselventil nach Anspruch 1 oder 2, 3. Gas exchange valve according to claim 1 or 2,
dadurch gekennzeichnet, dass characterized in that
die Nickel-Phosphor-Borcarbid-Schicht (4) 2 bis 7 Gew.-%, vorzugsweise 3 bis 5 Gew.-%, Borcarbid enthält. the nickel-phosphorus-boron carbide layer (4) contains 2 to 7% by weight, preferably 3 to 5% by weight, of boron carbide.
4. Gaswechselventil nach einem der Ansprüche 1 bis 3, 4. Gas exchange valve according to one of claims 1 to 3,
dadurch gekennzeichnet, dass characterized in that
die Nickel-Phosphor-Borcarbid-Schicht (4) eine Mischhärte zwischen 350 HV und 1500 HV, vorzugsweise zwischen 400 HV und 800 HV, aufweist. the nickel-phosphorus-boron carbide layer (4) has a mixed hardness between 350 HV and 1500 HV, preferably between 400 HV and 800 HV.
5. Gaswechselventil nach einem der vorhergehenden Ansprüche, 5. Gas exchange valve according to one of the preceding claims,
dadurch gekennzeichnet, dass characterized in that
die Nickel-Phosphor-Borcarbid-Schicht (4) einen mittleren Korndurchmesser d5o von weniger als 1 ,5 miti, vorzugsweise von 0,8 miti, aufweist. the nickel-phosphorus-boron carbide layer (4) has a mean grain diameter d 5 o of less than 1, 5 miti, preferably from 0.8 miti having.
6. Gaswechselventil nach einem der vorhergehenden Ansprüche, 6. Gas exchange valve according to one of the preceding claims,
dadurch gekennzeichnet, dass die Nickel-Phosphor-Borcarbid-Schicht (4) eine Schichtdicke (dNp) zwischen 5 bis 20 miti, vorzugweise zwischen 8 bis 12 miti, aufweist. characterized in that the nickel-phosphorus-boron carbide layer (4) has a layer thickness (d Np ) between 5 to 20 miti, preferably between 8 to 12 miti.
7. Gaswechselventil nach einem der vorhergehenden Ansprüche, 7. Gas exchange valve according to one of the preceding claims,
dadurch gekennzeichnet, dass characterized in that
die Nickel-Phosphor-Borcarbid-Schicht (4) entlang einer axialen Richtung (A) des Ventilschafts (3) eine Länge zwischen 60 mm und 140 mm aufweist. the nickel-phosphorus-boron carbide layer (4) has a length between 60 mm and 140 mm along an axial direction (A) of the valve stem (3).
8. Gaswechselventil nach einem der vorhergehenden Ansprüche, 8. Gas exchange valve according to one of the preceding claims,
dadurch gekennzeichnet, dass characterized in that
die Nickel-Phosphor-Borcarbid-Schicht (4) auf dem Ventilschaft (3) ausschließlich im Bereich (6) einer Ventilführung angeordnet ist. the nickel-phosphorus-boron carbide layer (4) on the valve stem (3) is arranged exclusively in the area (6) of a valve guide.
9. Gaswechselventil nach einem der vorhergehenden Ansprüche, 9. Gas exchange valve according to one of the preceding claims,
dadurch gekennzeichnet, dass characterized in that
die Nickel-Phosphor-Borcarbid-Schicht (4) auf dem Ventilschaft (3) vollständig um- laufend angeordnet ist. the nickel-phosphorus-boron carbide layer (4) on the valve stem (3) is arranged all the way round.
10. Gaswechselventil nach einem der vorhergehenden Ansprüche, 10. Gas exchange valve according to one of the preceding claims,
dadurch gekennzeichnet, dass characterized in that
der Ventilschaft (3) einen Durchmesser zwischen 5 mm und 10 mm aufweist. the valve stem (3) has a diameter between 5 mm and 10 mm.
11. Gaswechselventil nach einem der vorhergehenden Ansprüche, 11. Gas exchange valve according to one of the preceding claims,
dadurch gekennzeichnet, dass characterized in that
das Gaswechselventil (1 ) die martensitischen Stähle X45 und/oder X85 und/oder die austenitischen Stähle X50 und/oder Nickelbasiswerkstoffe NCF 3015 und/oder Nimonic80A enthält. the gas exchange valve (1) contains the martensitic steels X45 and / or X85 and / or the austenitic steels X50 and / or nickel-based materials NCF 3015 and / or Nimonic80A.
12. Gaswechselventil nach einem der vorhergehenden Ansprüche, 12. Gas exchange valve according to one of the preceding claims,
dadurch gekennzeichnet, dass zwischen dem Ventilschaft (3) und der Nickel-Phosphor-Borcarbid-Schicht (4) eine Haftschicht (5) mit einer Schichtdicke von weniger als 1 miti angeordnet ist. characterized in that an adhesive layer (5) with a layer thickness of less than 1 mm is arranged between the valve stem (3) and the nickel-phosphorus-boron carbide layer (4).
13. Gaswechselventil nach Anspruch 12, 13. Gas exchange valve according to claim 12,
dadurch gekennzeichnet, dass characterized in that
die Haftschicht (5) zwischen dem Ventilschaft (3) und der Nickel-Phosphor- Borcarbid-Schicht (4) Nickel enthält. the adhesive layer (5) between the valve stem (3) and the nickel-phosphorus-boron carbide layer (4) contains nickel.
14. Tribologisches System, 14. Tribological system,
- mit einer Ventilführung,  - with a valve guide,
- mit einem Gaswechselventil (1 ) nach einem der vorhergehenden Ansprüche.  - With a gas exchange valve (1) according to one of the preceding claims.
15. Brennkraftmaschine für ein Kraftfahrzeug, 15. Internal combustion engine for a motor vehicle,
- mit einem Gaswechselventil (1 ) nach einem der Ansprüche 1 bis 13, oder - With a gas exchange valve (1) according to one of claims 1 to 13, or
- mit einem tribologischen System nach Anspruch 14. - With a tribological system according to claim 14.
16. Verfahren zum Beschichten eines Gaswechselventils (1 ), umfassend einen Ventilschaft (3) und einen Ventilteller (2), insbesondere nach einem der Ansprüche 1 bis 13, 16. A method for coating a gas exchange valve (1) comprising a valve stem (3) and a valve disk (2), in particular according to one of claims 1 to 13,
gemäß welchem auf dem Ventilschaft (3) zumindest bereichsweise eine Nickel- Phosphor-Borcarbid-Schicht galvanisch (4) aufgebracht wird. According to which a nickel-phosphorus-boron carbide layer is electroplated (4) on the valve stem (3) at least in some areas.
17. Verfahren nach Anspruch 16, 17. The method according to claim 16,
dadurch gekennzeichnet, dass characterized in that
die Nickel-Phosphor-Borcarbid-Schicht (4) galvanisch mittels Stromdichten zwi- schen 30 A/dm2 und 200 A/dm2, insbesondere zwischen 90 A/dm2 und 120 A/dm2, aufgebracht wird. the nickel-phosphorus-boron carbide layer (4) is applied galvanically by means of current densities between 30 A / dm 2 and 200 A / dm 2 , in particular between 90 A / dm 2 and 120 A / dm 2 .
18. Verfahren nach Anspruch 16 oder 17, 18. The method according to claim 16 or 17,
dadurch gekennzeichnet, dass die aufgebrachte Nickel-Phosphor-Borcarbid-Schicht (4) 0,5 bis 5 Gew.-%, vor- zugsweise 1 ,5 bis 3 Gew.-%, Phosphor enthält. characterized in that the applied nickel-phosphorus-boron carbide layer (4) contains 0.5 to 5% by weight, preferably 1.5 to 3% by weight, of phosphorus.
19. Verfahren nach einem der Ansprüche 16 bis 18, 19. The method according to any one of claims 16 to 18,
dadurch gekennzeichnet, dass characterized in that
die aufgebrachte Nickel-Phosphor-Borcarbid-Schicht (4) 2 bis 7 Gew.-%, vor- zugsweise 3 bis 5 Gew.-%, Borcarbid enthält. the applied nickel-phosphorus-boron carbide layer (4) contains 2 to 7% by weight, preferably 3 to 5% by weight, of boron carbide.
20. Verfahren nach einem der Ansprüche 16 bis 19, 20. The method according to any one of claims 16 to 19,
dadurch gekennzeichnet, dass characterized in that
zwischen dem Ventilschaft (3) und der Nickel-Phosphor-Borcarbid-Schicht (4) eine Haftschicht (5) galvanisch aufgebracht wird. an adhesive layer (5) is applied galvanically between the valve stem (3) and the nickel-phosphorus-boron carbide layer (4).
21. Verfahren nach Anspruch 20, 21. The method according to claim 20,
dadurch gekennzeichnet, dass characterized in that
die Haftschicht (5) zwischen dem Ventilschaft (3) und der Nickel-Phosphor- Borcarbid-Schicht (4) galvanisch mittels Stromdichten zwischen 4 A/dm2 und 40 A/dm2, insbesondere zwischen 25 A/dm2 und 35 A/dm2, aufgebracht wird. the adhesive layer (5) between the valve stem (3) and the nickel-phosphorus-boron carbide layer (4) galvanically by means of current densities between 4 A / dm 2 and 40 A / dm 2 , in particular between 25 A / dm 2 and 35 A / dm 2 , is applied.
22. Verfahren nach Anspruch 20 oder 21 , 22. The method according to claim 20 or 21,
dadurch gekennzeichnet, dass characterized in that
die aufgebrachte Haftschicht (5) zwischen dem Ventilschaft (3) und der Nickel- Phosphor-Borcarbid-Schicht (4) Nickel enthält. the applied adhesive layer (5) between the valve stem (3) and the nickel-phosphorus-boron carbide layer (4) contains nickel.
**********
PCT/EP2019/078492 2018-10-24 2019-10-21 Gas exchange valve WO2020083808A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP19795136.1A EP3870740A1 (en) 2018-10-24 2019-10-21 Gas exchange valve

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102018218205.1 2018-10-24
DE102018218205.1A DE102018218205A1 (en) 2018-10-24 2018-10-24 Gas exchange valve

Publications (1)

Publication Number Publication Date
WO2020083808A1 true WO2020083808A1 (en) 2020-04-30

Family

ID=68387292

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2019/078492 WO2020083808A1 (en) 2018-10-24 2019-10-21 Gas exchange valve

Country Status (3)

Country Link
EP (1) EP3870740A1 (en)
DE (1) DE102018218205A1 (en)
WO (1) WO2020083808A1 (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5543029A (en) * 1994-04-29 1996-08-06 Fuji Oozx Inc. Properties of the surface of a titanium alloy engine valve
DE10228323A1 (en) * 2002-06-25 2004-01-29 Integran Technologies Inc., Toronto Patching process for degraded portion of metallic workpiece e.g. pipe and conduit, involves electroplating reinforcing metallic patch to cover degraded portion
DE102004047423B3 (en) * 2004-09-28 2006-02-09 AHC-Oberflächentechnik GmbH & Co. OHG Externally applied Nickel alloy and its use
DE102014225741A1 (en) 2014-12-12 2016-07-07 Mahle International Gmbh Gas exchange valve
EP3098334A1 (en) * 2015-05-29 2016-11-30 Metalcoating S.r.l. Electrolytic process for coating metal surfaces to provide high wear resistance
DE102015210552A1 (en) * 2015-06-09 2016-12-15 Mahle International Gmbh Process for coating a valve of an internal combustion engine

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE69408829T2 (en) * 1994-04-28 1998-10-22 Fuji Valve Improving the surface properties of a machine valve made of a titanium alloy
DE102017202585A1 (en) * 2016-02-17 2017-08-17 Mahle International Gmbh Internal combustion engine with at least one cylinder and with at least two hollow-head valves

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5543029A (en) * 1994-04-29 1996-08-06 Fuji Oozx Inc. Properties of the surface of a titanium alloy engine valve
DE10228323A1 (en) * 2002-06-25 2004-01-29 Integran Technologies Inc., Toronto Patching process for degraded portion of metallic workpiece e.g. pipe and conduit, involves electroplating reinforcing metallic patch to cover degraded portion
DE102004047423B3 (en) * 2004-09-28 2006-02-09 AHC-Oberflächentechnik GmbH & Co. OHG Externally applied Nickel alloy and its use
DE102014225741A1 (en) 2014-12-12 2016-07-07 Mahle International Gmbh Gas exchange valve
EP3098334A1 (en) * 2015-05-29 2016-11-30 Metalcoating S.r.l. Electrolytic process for coating metal surfaces to provide high wear resistance
DE102015210552A1 (en) * 2015-06-09 2016-12-15 Mahle International Gmbh Process for coating a valve of an internal combustion engine

Also Published As

Publication number Publication date
EP3870740A1 (en) 2021-09-01
DE102018218205A1 (en) 2020-04-30

Similar Documents

Publication Publication Date Title
WO2011018252A1 (en) Sliding element, in particular a piston ring, having a coating
DE102014008844A1 (en) Brake disc for a motor vehicle
WO2016198205A1 (en) Method for coating a valve of an internal combustion engine
EP2825682B1 (en) Piston ring with chromium solid particle wear-prevention layer and corrosion-resistant flank surface
EP3061852A2 (en) Gas exchange valve
DE4112892C2 (en) piston ring
DE10061750B4 (en) Tungsten wear protection layer for piston rings
DE10125894B4 (en) valve means
EP2829713B1 (en) Workpiece with a recess for holding a piston
EP3973206B1 (en) Method for producing a friction brake body for a friction brake
DE102013213268A1 (en) Built hollow valve
EP3870740A1 (en) Gas exchange valve
DE202015100601U1 (en) Seat valve for at least partially closing and opening a conduit system
DE102011000793A1 (en) Self-sharpening drilling tool, particularly spiral drill, has head portion that makes free surfaces and clamping surfaces at main cutting edges
EP1437537A2 (en) Drive sealing
DE102015014192A1 (en) functional layer
DE112009000308T5 (en) Spark-erosive coating method and thereby used green compact electrode
EP3455468B1 (en) Gas exchange valve
DE102019213461B3 (en) Friction brake body for a friction brake, friction brake and method for producing a friction brake body
EP4029966A1 (en) Method for producing a coated grey cast iron brake disc
DE10256063A1 (en) Process for coating piston rings for internal combustion engines
DE102019207267A1 (en) Gas exchange valve for an internal combustion engine
DE102018103423A1 (en) Cone piece for valves of combustion engines with nickel-phosphor coating
EP1522610B1 (en) Method for the production of a wear-resistant layer
DE102012224269A1 (en) Component of a fuel injection system

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19795136

Country of ref document: EP

Kind code of ref document: A1

DPE2 Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101)
NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2019795136

Country of ref document: EP

Effective date: 20210525