EP0462850A1 - Method of making aluminium alloy castings containing an insert and cylinder head of internal combustion engine obtained thereby - Google Patents
Method of making aluminium alloy castings containing an insert and cylinder head of internal combustion engine obtained thereby Download PDFInfo
- Publication number
- EP0462850A1 EP0462850A1 EP91401295A EP91401295A EP0462850A1 EP 0462850 A1 EP0462850 A1 EP 0462850A1 EP 91401295 A EP91401295 A EP 91401295A EP 91401295 A EP91401295 A EP 91401295A EP 0462850 A1 EP0462850 A1 EP 0462850A1
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- EP
- European Patent Office
- Prior art keywords
- insert
- cylinder head
- nickel
- treatment
- alloy
- 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.)
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D19/00—Casting in, on, or around objects which form part of the product
- B22D19/0081—Casting in, on, or around objects which form part of the product pretreatment of the insert, e.g. for enhancing the bonding between insert and surrounding cast metal
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D19/00—Casting in, on, or around objects which form part of the product
- B22D19/0009—Cylinders, pistons
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D19/00—Casting in, on, or around objects which form part of the product
- B22D19/14—Casting in, on, or around objects which form part of the product the objects being filamentary or particulate in form
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F1/24—Cylinder heads
- F02F1/26—Cylinder heads having cooling means
- F02F1/36—Cylinder heads having cooling means for liquid cooling
- F02F1/38—Cylinder heads having cooling means for liquid cooling the cylinder heads being of overhead valve type
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F2001/008—Stress problems, especially related to thermal stress
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F1/24—Cylinder heads
- F02F2001/244—Arrangement of valve stems in cylinder heads
- F02F2001/247—Arrangement of valve stems in cylinder heads the valve stems being orientated in parallel with the cylinder axis
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F1/24—Cylinder heads
- F02F2001/248—Methods for avoiding thermal stress-induced cracks in the zone between valve seat openings
Definitions
- the invention generally relates to a method for manufacturing cast aluminum alloy parts comprising an insert.
- the present invention finds application in particular in the manufacture of an internal combustion engine cylinder head, provided with an insert.
- a method of manufacturing a casting comprising a ceramic insert is known. It consists of depositing on the insert, a flexible mattress of ceramic fibers, then placing the insert in a mold and finally pouring the metal into the mold.
- the alloy part forming the cylinder head undergoes large temperature variations during engine operation, the maximum temperature being able to reach 350 ° C.
- the part of the cylinder head forming the inter-valve seat areas deteriorates by cracking, deforms when hot and its service life decreases accordingly.
- the present invention aims to overcome the drawbacks mentioned above by proposing a method for manufacturing cast aluminum alloy parts comprising an insert, where the insert is composed of a composite material with a metallic matrix, which is made up by a reinforcement based on alumina or alumina-silica fibers forming felt, impregnated under high pressure with an aluminum alloy different from or identical to the casting alloy.
- the fixing, in particular chemical, between the insert and the cast alloy part must be perfect.
- an impermeable and non-fusible alumina layer covers the entire surface of the insert and presents an obstacle to the creation of a chemical bond between the insert and the casting alloy part.
- the invention therefore also aims to create a chemical bond at the insert - part interface.
- the invention provides a method for manufacturing cast aluminum alloy parts comprising an insert, which more precisely consists in subjecting a matrix alloy surface of at least one face of the insert, to a treatment zincate type chemical, followed by at least one electrolytic treatment such as a nickel coating.
- the chemical treatment with zincate forms on the aforementioned surface a layer of zinc or of zinc-iron alloy containing approximately 15% of iron.
- the electrolytic treatment is carried out from a nickel sulphate or sulphamate solution.
- the aforementioned surface of the insert undergoes a second electrolytic treatment such as a silver coating.
- the invention also relates to an internal combustion engine cylinder head, provided with at least one insert, the cylinder head made of cast aluminum alloy being produced by the method according to the invention.
- Figure 1 shows a schematic section of the insert formed of a composite material before the treatment of its surface.
- FIG. 2 represents a schematic section of this same insert after the treatment of its surface.
- FIG. 3 represents a plan view of the insert after impregnation and before introduction into the mold.
- Figure 4 is a sectional view of the insert along line IV-IV.
- FIG. 5 represents a partial view from below of an internal combustion engine cylinder head.
- Figure 6 shows a partial section of the cylinder head shown in Figure 5, along the line VI-VI.
- FIG. 7 shows a partial perspective view of the cylinder head shown in Figure 5 in the direction VII.
- an insert is placed within the part.
- This insert is made beforehand from composite material which consists on the one hand of a reinforcing material based on ceramic fibers such as for example alumina or alumina-silica fibers, which are entangled with the way of a felt whose cohesion is ensured by an inorganic binder, such as for example a silica binder, and on the other hand of an aluminum-based matrix and more precisely of an aluminum alloy different from or identical to the aluminum alloy of the casting.
- This aluminum alloy forming the matrix is also called a matrix alloy.
- This composite material is produced by impregnating the reinforcing material under high pressure with the aluminum alloy or matrix alloy in the liquid state.
- An example of a material of this type includes a reinforcement of short alumina fibers, an AS5U4G2 matrix according to AFNOR standards.
- the face d it will be used as described below to create a chemical bond at the insert-part interface, which allows chemical attachment between the part and the insert.
- the insert thus produced is then subjected to chemical treatments.
- the surface of the face d of the insert will undergo chemical treatment and at least electrolytic treatment.
- the face d described above has on its surface an impermeable and non-fusible alumina layer which hinders the subsequent chemical fixation between the insert and the part.
- the surface d is subjected to a chemical treatment of the zincate type and preferably of the zinc-iron type.
- This treatment is carried out using a solution containing zinc oxide, sodium hydroxide, double potassium and sodium tartrate and ferric chloride.
- the main mechanisms used in the reaction are as follows.
- this layer has an iron content of around 15%.
- this layer shown in f is very thin, having a thickness of less than 1 micron.
- this layer f The role of this layer f is to prevent the alumina layer from reforming on the surface of the face d of the insert, it therefore prevents surface reoxidation of the face d of the insert.
- the surface of the insert that is to say this face f, undergoes an electrolytic treatment to form a coating.
- a conventional coating is for example an electrolytic deposit of nickel.
- the treatment is carried out in a bath containing nickel sulphate or sulphamate, nickel chloride, and boric acid.
- a layer g a few microns thick is formed, thereby protecting layer f and limiting the surface reoxidation of the insert before casting the part.
- this layer f allows the diffusion of nickel in the aluminum casting alloy thus creating the chemical bond in the casting step of the part.
- This coating is produced from a bath typically containing: double cyanide of silver and potassium, potassium cyanide and potassium carbonate.
- the silver layer h thus obtained, a thickness of a few microns, better protects the surface of the insert than nickel by more effectively limiting the reoxidation of the surface of the insert before casting.
- this silver layer h improves the chemical bond at the insert-part interface because the diffusion coefficient of silver in aluminum is higher than that of nickel in aluminum.
- the faces of the insert thus prepared and treated ensure both mechanical attachment and a chemical bond at the insert - part interface.
- the insert which will be placed in the mold for the casting of the part may be in a temporary form, sometimes necessary to maintain it motionless during casting. In this case, it will be machined after the casting step, in order to reach its final shape.
- the insert comprising all the coating layers f and g and optionally h on its face d, is positioned inside the mold. The latter is then closed and the casting of the part can begin.
- the aluminum alloy of the part is cast according to specific parameters such as the temperature of the insert in the mold, the temperature of casting of the liquid alloy and the quantity of alloy which, in contact with the insert , heats it for the duration of the casting. All of these parameters taken in combination acts on the creation of a chemical bond at the insert - part interface. An optimal combination of parameters generates a very good chemical bond.
- the part thus cast comprising an insert is then removed from the mold.
- the method of manufacturing an alloy part comprising an insert according to the invention finds application in the automotive industry.
- FIG. 3 An example of an insert intended to be introduced into a cylinder head is shown in FIG. 3. It has lateral faces 2 and 3 of concave shape, where the valves will be housed in the inter-seat zones 4 and 5.
- the insert in cross section according to Figure 4 has a trapezoidal section.
- the undercuts 6 and 7 are used for the mechanical fixing of the insert, and the face 8 which will undergo the chemical and electrolytic treatments according to the invention, is used for the chemical fixing between the insert and the part.
- the aluminum alloy of the cylinder head is then poured, for example by gravity, onto this insert of composite material which has undergone the chemical and electrolytic treatments mentioned above.
- an insert (or more) is (are) for example disposed (s) at the areas between the valve seats.
- the insert 1 is housed between two inter-seat zones of valves 4 and 5 inside the cylinder head 9. Valves will be housed in the spaces 10 and 11.
- Figure 6 is a partial section of the cylinder head shown in Figure 5, shows the insert 1 fixed in particular by its face 8 to the cylinder head 9 by the chemical bond generated by the method of manufacturing the cylinder head.
- the insert 1 is positioned between the spaces 10 and 11 or also valve ducts, one inlet duct, the other exhaust duct.
- valve heads 12 and 13 respectively are received against the insert 1 in the conduits 10 and 11, coming into contact with the insert 1 in the zones 4 and 5.
- FIG. 7 illustrates the positioning of the insert fixed within the cylinder head.
- the valve heads 12 and 13 can move on either side of the insert 1.
- the thus produced aluminum alloy cylinder head comprising an insert in at least one of its inter-valve seat areas, prolongs the life of the cylinder head by clearly improving the life in thermal fatigue and the elastic limit in temperature of these inter-valve seat areas.
- the cylinder head then withstands temperature variations much better during engine cycles, compared to conventional cylinder heads.
- the invention also finds application in the manufacture of other parts made of cast aluminum alloy.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Cylinder Crankcases Of Internal Combustion Engines (AREA)
- Manufacture Of Alloys Or Alloy Compounds (AREA)
Abstract
Description
L'invention concerne généralement un procédé de fabrication de pièces en alliage d'aluminium coulé comportant un insert.The invention generally relates to a method for manufacturing cast aluminum alloy parts comprising an insert.
La présente invention trouve application notamment dans la fabrication d'une culasse de moteur à combustion interne, munie d'un insert.The present invention finds application in particular in the manufacture of an internal combustion engine cylinder head, provided with an insert.
Dans la métallurgie des alliages de fonderie, un procédé de fabrication d'une pièce coulée comportant un insert en matière céramique est connu. Il consiste à déposer sur l'insert, un matelas souple de fibres en matière céramique, puis à placer l'insert dans un moule et enfin à couler le métal dans le moule.In the metallurgy of foundry alloys, a method of manufacturing a casting comprising a ceramic insert is known. It consists of depositing on the insert, a flexible mattress of ceramic fibers, then placing the insert in a mold and finally pouring the metal into the mold.
Or, les pièces ainsi obtenues, sont souvent soumises dans leur utilisation, à des cycles thermiques ; et sous l'effet des températures élevées, ces pièces atteignent rapidement leur limite de rupture, leur limite à la fatigue thermique et leur limite élastique à température du matériau considéré.However, the parts thus obtained are often subjected in their use to thermal cycles; and under the effect of the high temperatures, these parts quickly reach their breaking limit, their limit to thermal fatigue and their elastic limit at temperature of the material considered.
Dans le cas particulier des culasses de moteur, la pièce en alliage formant la culasse subit de fortes variations de température pendant le fonctionnement du moteur, la température maximale pouvant atteindre 350°C. La partie de la culasse formant les zones inter-sièges de soupape se détériore par fissuration, se déforme à chaud et sa durée de vie diminue en conséquence.In the particular case of engine cylinder heads, the alloy part forming the cylinder head undergoes large temperature variations during engine operation, the maximum temperature being able to reach 350 ° C. The part of the cylinder head forming the inter-valve seat areas deteriorates by cracking, deforms when hot and its service life decreases accordingly.
La présente invention a pour but de pallier les inconvénients mentionnés ci-dessus en proposant un procédé de fabrication de pièces en alliage d'aluminium coulé comportant un insert, où l'insert est composé d'un matériau composite à matrice métallique, qui est constitué par un renfort à base de fibres d'alumine ou d'alumine-silice formant feutre, imprégné sous haute pression par un alliage d'aluminium différent de ou identique à l'alliage de coulée.The present invention aims to overcome the drawbacks mentioned above by proposing a method for manufacturing cast aluminum alloy parts comprising an insert, where the insert is composed of a composite material with a metallic matrix, which is made up by a reinforcement based on alumina or alumina-silica fibers forming felt, impregnated under high pressure with an aluminum alloy different from or identical to the casting alloy.
Par ailleurs, dans ce procédé, la fixation, notamment chimique, entre l'insert et la pièce en alliage coulé doit être parfaite. En effet, une couche d'alumine imperméable et non fusible recouvre toute la surface de l'insert et présente un obstacle à la création d'une liaison chimique entre l'insert et la pièce en alliage de coulée.Furthermore, in this process, the fixing, in particular chemical, between the insert and the cast alloy part must be perfect. Indeed, an impermeable and non-fusible alumina layer covers the entire surface of the insert and presents an obstacle to the creation of a chemical bond between the insert and the casting alloy part.
L'invention a donc également pour but de créer une liaison chimique à l'interface insert - pièce.The invention therefore also aims to create a chemical bond at the insert - part interface.
A cet effet, l'invention propose un procédé de fabrication de pièces en alliage d'aluminium coulé comportant un insert, qui consiste plus précisément à faire subir à une surface en alliage matriciel d'au moins une face de l'insert, un traitement chimique du type zincate, suivi d'au moins un traitement électrolytique tel qu'un revêtement de nickel.To this end, the invention provides a method for manufacturing cast aluminum alloy parts comprising an insert, which more precisely consists in subjecting a matrix alloy surface of at least one face of the insert, to a treatment zincate type chemical, followed by at least one electrolytic treatment such as a nickel coating.
Suivant une caractéristique de l'invention, le traitement chimique au zincate forme sur la surface précitée une couche de zinc ou d'alliage zinc - fer contenant environ 15% de fer.According to a characteristic of the invention, the chemical treatment with zincate forms on the aforementioned surface a layer of zinc or of zinc-iron alloy containing approximately 15% of iron.
Suivant une autre caractéristique de l'invention, le traitement électrolytique est effectué à partir d'une solution de sulfate ou de sulfamate de nickel.According to another characteristic of the invention, the electrolytic treatment is carried out from a nickel sulphate or sulphamate solution.
Selon une variante de l'invention, la surface précitée de l'insert subit un second traitement électrolytique tel qu'un revêtement d'argent.According to a variant of the invention, the aforementioned surface of the insert undergoes a second electrolytic treatment such as a silver coating.
L'invention a également pour objet une culasse de moteur à combustion interne, munie d'au moins un insert, la culasse en alliage d'aluminium coulé étant fabriquée par le procédé selon l'invention.The invention also relates to an internal combustion engine cylinder head, provided with at least one insert, the cylinder head made of cast aluminum alloy being produced by the method according to the invention.
D'autres caractéristiques et avantages de l'invention apparaîtront mieux à la lecture de la description détaillée qui suit et qui se réfère aux dessins annexés, donnés uniquement à titre d'exemple, dans lesquels.Other characteristics and advantages of the invention will appear better on reading the detailed description which follows and which refers to the appended drawings, given solely by way of example, in which.
La figure 1 représente une coupe schématique de l'insert formé d'un matériau composite avant le traitement de sa surface.Figure 1 shows a schematic section of the insert formed of a composite material before the treatment of its surface.
La figure 2 représente une coupe schématique de ce même insert après le traitement de sa surface.FIG. 2 represents a schematic section of this same insert after the treatment of its surface.
La figure 3 représente une vue en plan de l'insert après imprégnation et avant introduction dans le moule.FIG. 3 represents a plan view of the insert after impregnation and before introduction into the mold.
La figure 4 est une vue en coupe de l'insert suivant la ligne IV-IV.Figure 4 is a sectional view of the insert along line IV-IV.
La figure 5 représente une vue partielle et de dessous d'une culasse de moteur à combustion interne.FIG. 5 represents a partial view from below of an internal combustion engine cylinder head.
La figure 6 représente une coupe partielle de la culasse représentée à la figure 5, suivant la ligne VI-VI.Figure 6 shows a partial section of the cylinder head shown in Figure 5, along the line VI-VI.
La figure 7 représente une vue partielle en perspective de la culasse représentée à la figure 5 suivant la direction VII.7 shows a partial perspective view of the cylinder head shown in Figure 5 in the direction VII.
Suivant le procédé de fabrication de pièces en alliage coulé selon l'invention, un insert est disposé au sein de la pièce.According to the method for manufacturing cast alloy parts according to the invention, an insert is placed within the part.
Cet insert est fabriqué au préalable à partir de matériau composite qui se compose d'une part d'un matériau de renfort à base de fibres céramiques telles que par exemple des fibres d'alumine ou d'alumine - silice, qui sont enchevêtrées à la manière d'un feutre dont la cohésion est assurée par un liant minéral, tel que par exemple un liant de silice, et d'autre part d'une matrice à base d'aluminium et plus précisément d'un alliage d'aluminium différent de ou identique à l'alliage d'aluminium de la pièce coulée. Cet alliage d'aluminium formant la matrice est encore appelé alliage matriciel. Ce matériau composite est fabriqué en imprégnant sous haute pression le matériau de renfort par l'alliage d'aluminium ou alliage matriciel à l'état liquide.This insert is made beforehand from composite material which consists on the one hand of a reinforcing material based on ceramic fibers such as for example alumina or alumina-silica fibers, which are entangled with the way of a felt whose cohesion is ensured by an inorganic binder, such as for example a silica binder, and on the other hand of an aluminum-based matrix and more precisely of an aluminum alloy different from or identical to the aluminum alloy of the casting. This aluminum alloy forming the matrix is also called a matrix alloy. This composite material is produced by impregnating the reinforcing material under high pressure with the aluminum alloy or matrix alloy in the liquid state.
Un procédé de fabrication de ce matériau composite est décrit notamment dans la demande de brevet européen déposée sous le No. 89402986.7.A method of manufacturing this composite material is described in particular in the European patent application filed under No. 89402986.7.
Un exemple de matériau de ce type comprend un renfort de fibres courtes d'alumine, une matrice AS5U4G2 selon les normes AFNOR.An example of a material of this type includes a reinforcement of short alumina fibers, an AS5U4G2 matrix according to AFNOR standards.
En se reportant à la figure 1, l'insert 1 comprend :
- une partie centrale a, qui est formée de matériau composite renforcé de fibres céramiques imprégnées par un alliage d'aluminium ;
- une face b en matériau composite où les fibres céramiques affleurent, c'est la face utile de l'insert qui permet l'exploitation optimale des propriétés du matériau composite, cette face n'entrera pas en contact avec l'alliage de coulée ;
- une face c et une face d qui sont constituées par une surépaisseur d'alliage d'aluminium ou encore d'alliage matriciel, l'alliage d'aluminium sans fibres affleure donc les faces c et d.
- a central part a, which is formed of composite material reinforced with ceramic fibers impregnated with an aluminum alloy;
- a face b of composite material where the ceramic fibers are flush, it is the useful face of the insert which allows the optimal exploitation of the properties of the composite material, this face will not come into contact with the casting alloy;
- a face c and a face d which are constituted by an excess thickness of aluminum alloy or even of matrix alloy, the aluminum alloy without fibers is therefore flush with the faces c and d.
La face c de par sa contre-dépouille, servira uniquement à l'accrochage mécanique entre l'insert et la pièce coulée.The side c by its undercut, will only be used for mechanical attachment between the insert and the casting.
Quant à la face d, elle sera utilisée comme décrit ci-après pour créer une liaison chimique à l'interface insert - pièce, ce qui permet la fixation chimique entre la pièce et l'insert.As for the face d, it will be used as described below to create a chemical bond at the insert-part interface, which allows chemical attachment between the part and the insert.
L'insert ainsi fabriqué est ensuite soumis à des traitements d'ordre chimique.The insert thus produced is then subjected to chemical treatments.
Plus précisément, la surface de la face d de l'insert va subir un traitement chimique et au moins un traitement électrolytique.More specifically, the surface of the face d of the insert will undergo chemical treatment and at least electrolytic treatment.
En effet, la face d décrite ci-dessus présente sur sa surface une couche d'alumine imperméable et non fusible qui entrave la fixation chimique ultérieure entre l'insert et la pièce.Indeed, the face d described above has on its surface an impermeable and non-fusible alumina layer which hinders the subsequent chemical fixation between the insert and the part.
Pour ce faire, il est nécessaire d'éliminer cette couche d'alumine.To do this, it is necessary to remove this layer of alumina.
A cet effet, la surface d est soumise à un traitement chimique du type zincate et de préférence du type zinc - fer.To this end, the surface d is subjected to a chemical treatment of the zincate type and preferably of the zinc-iron type.
Ce traitement est réalisé au moyen d'une solution contenant de l'oxyde de zinc, de la soude, du tartrate double de potassium et de sodium et du chlorure ferrique.This treatment is carried out using a solution containing zinc oxide, sodium hydroxide, double potassium and sodium tartrate and ferric chloride.
Les mécanismes mis en oeuvre dans la réaction sont pour les principaux comme suit.The main mechanisms used in the reaction are as follows.
Les réactions du type anodique :
Dans le cas de l'alliage zinc - fer, cette couche a une teneur en fer d'environ 15%.In the case of the zinc - iron alloy, this layer has an iron content of around 15%.
En référence à la figure 2, cette couche représentée en f est très fine, ayant une épaisseur inférieure à 1 micron.Referring to Figure 2, this layer shown in f is very thin, having a thickness of less than 1 micron.
Cette couche f a pour rôle d'empêcher la couche d'alumine de se reformer en surface de la face d de l'insert, elle évite donc la réoxydation superficielle de la face d de l'insert.The role of this layer f is to prevent the alumina layer from reforming on the surface of the face d of the insert, it therefore prevents surface reoxidation of the face d of the insert.
Mais cette couche peu épaisse est fragile et doit être protégée afin de faciliter les manipulations et la conservation de l'état de la surface de l'insert.However, this thin layer is fragile and must be protected in order to facilitate handling and the preservation of the state of the surface of the insert.
De ce fait, la surface de l'insert, c'est-à-dire cette face f, subit un traitement électrolytique pour former un revêtement.Therefore, the surface of the insert, that is to say this face f, undergoes an electrolytic treatment to form a coating.
Un revêtement classique est par exemple un dépôt électrolytique de nickel.A conventional coating is for example an electrolytic deposit of nickel.
Le traitement se fait dans un bain contenant du sulfate ou du sulfamate de nickel, du chlorure de nickel, et de l'acide borique.The treatment is carried out in a bath containing nickel sulphate or sulphamate, nickel chloride, and boric acid.
Une couche g de quelques microns d'épaisseur se forme, protégeant ainsi la couche f et limitant la réoxydation superficielle de l'insert avant la coulée de la pièce. De plus, cette couche f permet la diffusion de nickel dans l'alliage d'aluminium de coulée créant ainsi la liaison chimique à l'étape de coulée de la pièce.A layer g a few microns thick is formed, thereby protecting layer f and limiting the surface reoxidation of the insert before casting the part. In addition, this layer f allows the diffusion of nickel in the aluminum casting alloy thus creating the chemical bond in the casting step of the part.
Enfin, dans des conditions de coulée difficiles, il est possible de placer sur la couche g, un revêtement supplémentaire par un dépôt électrolytique d'argent.Finally, under difficult casting conditions, it is possible to place on the layer g, an additional coating by an electrolytic deposit of silver.
Ce revêtement est réalisé à partir d'un bain contenant de manière typique : du cyanure double d'argent et de potassium, du cyanure de potassium et du carbonate de potassium.This coating is produced from a bath typically containing: double cyanide of silver and potassium, potassium cyanide and potassium carbonate.
La couche h en argent ainsi obtenue, d'une épaisseur de quelques microns, protège mieux que le nickel la surface de l'insert en limitant plus efficacement la réoxydation de la surface de l'insert avant la coulée. Par ailleurs, cette couche h en argent améliore la liaison chimique à l'interface insert - pièce du fait que le coefficient de diffusion de l'argent dans l'aluminium est plus élevé que celui du nickel dans l'aluminium.The silver layer h thus obtained, a thickness of a few microns, better protects the surface of the insert than nickel by more effectively limiting the reoxidation of the surface of the insert before casting. In addition, this silver layer h improves the chemical bond at the insert-part interface because the diffusion coefficient of silver in aluminum is higher than that of nickel in aluminum.
Les faces de l'insert ainsi préparées et traitées assurent à la fois un accrochage mécanique et une liaison chimique à l'interface insert - pièce.The faces of the insert thus prepared and treated ensure both mechanical attachment and a chemical bond at the insert - part interface.
Toutes les formes d'insert peuvent être envisagées.All forms of insert can be considered.
L'insert qui va être placé dans le moule pour la coulée de la pièce, peut être sous une forme provisoire, parfois nécessaire pour le maintenir immobile au cours de la coulée. Dans ce cas, il sera usiné après l'étape de coulée, afin d'atteindre sa forme définitive.The insert which will be placed in the mold for the casting of the part, may be in a temporary form, sometimes necessary to maintain it motionless during casting. In this case, it will be machined after the casting step, in order to reach its final shape.
Puis, l'étape d'insertion proprement dite est envisagée.Then, the actual insertion step is considered.
Toutes les configurations de pièces sont possibles, les moules étant préparés en conséquence.All configurations of parts are possible, the molds being prepared accordingly.
L'insert comportant l'ensemble des couches de revêtement f et g et éventuellement h sur sa face d, est positionné à l'intérieur du moule. Ce dernier est ensuite fermé et la coulée de la pièce peut commencer.The insert comprising all the coating layers f and g and optionally h on its face d, is positioned inside the mold. The latter is then closed and the casting of the part can begin.
Toutes les techniques de coulée d'alliages légers actuelles et futures peuvent être appliquées ici.All current and future light alloy casting techniques can be applied here.
L'alliage d'aluminium de la pièce est coulé suivant des paramètres spécifiques tels que la température de l'insert dans le moule, la température de coulée de l'alliage liquide et la quantité d'alliage qui, au contact de l'insert, réchauffe celui-ci pendant la durée de la coulée. L'ensemble de ces paramètres pris en combinaison agit sur la création d'une liaison chimique à l'interface insert - pièce. Une combinaison optimale des paramètres engendre une très bonne liaison chimique.The aluminum alloy of the part is cast according to specific parameters such as the temperature of the insert in the mold, the temperature of casting of the liquid alloy and the quantity of alloy which, in contact with the insert , heats it for the duration of the casting. All of these parameters taken in combination acts on the creation of a chemical bond at the insert - part interface. An optimal combination of parameters generates a very good chemical bond.
La pièce ainsi coulée comportant un insert, est ensuite démoulée.The part thus cast comprising an insert is then removed from the mold.
Le procédé de fabrication d'une pièce en alliage comportant un insert selon l'invention, trouve application dans l'industrie automobile.The method of manufacturing an alloy part comprising an insert according to the invention finds application in the automotive industry.
En particulier des culasses de moteur à combustion interne, en alliage d'aluminium, sont ainsi produites.In particular cylinder heads of internal combustion engine, made of aluminum alloy, are thus produced.
Un exemple d'insert prévu pour être introduit dans une culasse, est représenté à la figure 3. Il présente des faces latérales 2 et 3 de forme concave, où viendront se loger les soupapes dans les zones inter-sièges 4 et 5. L'insert en coupe transversale selon la figure 4, a une section trapézoïdale. Les contre-dépouilles 6 et 7 servent à la fixation mécanique de l'insert, et la face 8 qui subira les traitements chimique et électrolytique selon l'invention, sert à la fixation chimique entre l'insert et la pièce.An example of an insert intended to be introduced into a cylinder head is shown in FIG. 3. It has lateral faces 2 and 3 of concave shape, where the valves will be housed in the
L'alliage d'aluminium de la culasse est ensuite coulé par exemple par gravité sur cet insert en matériau composite qui a subi les traitements chimiques et électrolytiques mentionnés précédemment.The aluminum alloy of the cylinder head is then poured, for example by gravity, onto this insert of composite material which has undergone the chemical and electrolytic treatments mentioned above.
Dans le cas des culasses, un insert (ou plus) est (sont) par exemple disposé (s) au niveau des zones entre les sièges de soupape.In the case of cylinder heads, an insert (or more) is (are) for example disposed (s) at the areas between the valve seats.
En référence à la figure 5, l'insert 1 vient se loger entre deux zones inter-sièges de soupapes 4 et 5 à l'intérieur de la culasse 9. Des soupapes viendront se loger dans les espaces 10 et 11.With reference to FIG. 5, the
La figure 6 étant une coupe partielle de la culasse représentée à la figure 5, montre bien l'insert 1 fixé notamment par sa face 8 à la culasse 9 par la liaison chimique engendrée par le procédé de fabrication de la culasse.Figure 6 is a partial section of the cylinder head shown in Figure 5, shows the
L'insert 1 est positionné entre les espaces 10 et 11 ou encore conduits de soupape, l'un conduit d'admission, l'autre conduit d'échappement.The
Les têtes de soupape respectivement 12 et 13 viennent se loger contre l'insert 1 dans les conduits 10 et 11, en entrant en contact avec l'insert 1 dans les zones 4 et 5.The valve heads 12 and 13 respectively are received against the
De même, la vue en perspective de la figure 7 illustre bien le positionnement de l'insert fixé au sein de la culasse. Les têtes de soupapes 12 et 13 peuvent se déplacer de part et d'autre de l'insert 1.Likewise, the perspective view of FIG. 7 illustrates the positioning of the insert fixed within the cylinder head. The valve heads 12 and 13 can move on either side of the
La culasse en alliage d'aluminium ainsi fabriquée comprenant un insert dans au moins une de ses zones inter-sièges de soupapes, prolonge la durée de vie de la culasse en améliorant nettement la durée de vie en fatigue thermique et la limite élastique en température de ces zones inter-sièges de soupapes.The thus produced aluminum alloy cylinder head comprising an insert in at least one of its inter-valve seat areas, prolongs the life of the cylinder head by clearly improving the life in thermal fatigue and the elastic limit in temperature of these inter-valve seat areas.
La culasse résiste alors beaucoup mieux aux variations de températures au cours des cycles du moteur, comparée aux culasses classiques.The cylinder head then withstands temperature variations much better during engine cycles, compared to conventional cylinder heads.
L'invention trouve également application dans la fabrication d'autres pièces en alliage d'aluminium coulé.The invention also finds application in the manufacture of other parts made of cast aluminum alloy.
Claims (9)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR9007667 | 1990-06-19 | ||
FR9007667A FR2663250A1 (en) | 1990-06-19 | 1990-06-19 | METHOD FOR MANUFACTURING ALUMINUM COLOR ALLOY PARTS COMPRISING AN INSERT AND CULASSE OF AN INTERNAL COMBUSTION ENGINE OBTAINED BY THIS PROCESS. |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0462850A1 true EP0462850A1 (en) | 1991-12-27 |
EP0462850B1 EP0462850B1 (en) | 1998-08-26 |
Family
ID=9397788
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19910401295 Expired - Lifetime EP0462850B1 (en) | 1990-06-19 | 1991-05-17 | Method of making aluminium alloy castings containing an insert and cylinder head of internal combustion engine obtained thereby |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0462850B1 (en) |
DE (1) | DE69130038T2 (en) |
FR (1) | FR2663250A1 (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2736968A1 (en) * | 1995-07-18 | 1997-01-24 | Renault | Housing area for valve seats in IC engine cylinder head - has thermal screen fitted over landing area between adjacent valve seat housings, with screen held in place by side panels, fitting between valve seat housings |
WO2004018718A1 (en) * | 2002-08-20 | 2004-03-04 | 3M Innovative Properties Company | Metal matrix composites, and methods for making the same |
EP1460151A1 (en) * | 2003-03-19 | 2004-09-22 | Ford Global Technologies, LLC, A subsidary of Ford Motor Company | Cylinder head for reciprocating internal combustion engines |
WO2006023080A1 (en) * | 2004-07-29 | 2006-03-02 | 3M Innovative Properties Company | Metal matrix composites, and methods for making the same |
WO2006023069A1 (en) * | 2004-07-29 | 2006-03-02 | 3M Innovative Properties Company | Metal matrix composites, and methods for making the same |
WO2006023070A1 (en) * | 2004-07-29 | 2006-03-02 | 3M Innovative Properties Company | Metal matrix composites, and methods for making the same |
WO2007137314A2 (en) | 2006-05-26 | 2007-12-06 | Avl List Gmbh | Cylinder head for an internal combustion engine |
AT502971B1 (en) * | 2006-12-07 | 2008-05-15 | Avl List Gmbh | CYLINDER HEAD FOR AN INTERNAL COMBUSTION ENGINE |
CN114645796A (en) * | 2022-01-13 | 2022-06-21 | 爱柯迪股份有限公司 | Silicon nitride fiber reinforced aluminum alloy engine cylinder sleeve and preparation method thereof |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6443211B1 (en) | 1999-08-31 | 2002-09-03 | Cummins Inc. | Mettallurgical bonding of inserts having multi-layered coatings within metal castings |
FR2831845B1 (en) * | 2001-11-07 | 2004-05-21 | Peugeot Citroen Automobiles Sa | METHOD AND DEVICE FOR CASTING A METAL PART COMPRISING A REINFORCING ELEMENT |
DE102012104820B4 (en) * | 2012-06-04 | 2014-10-09 | Actech Gmbh | Process for the production of composite castings |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2439870A1 (en) * | 1973-08-20 | 1975-03-06 | Ford Werke Ag | COMPOSITION ROTOR HOUSING WITH WEAT-RESISTANT COATING |
GB2173436A (en) * | 1985-03-29 | 1986-10-15 | Kolbenschmidt Ag | Composite casting process |
EP0203198A1 (en) * | 1984-11-07 | 1986-12-03 | Mitsubishi Jidosha Kogyo Kabushiki Kaisha | Method of reinforcing a metallic article |
EP0246423A2 (en) * | 1986-05-23 | 1987-11-25 | Vereinigte Aluminium-Werke Aktiengesellschaft | Method of and installation for resistant connection of ceramic mould parts with metals |
WO1989009669A1 (en) * | 1988-04-15 | 1989-10-19 | Sandvik Australia Pty. Limited | Composite hard metal-metal components |
EP0384045A2 (en) * | 1989-02-22 | 1990-08-29 | TEMAV S.p.A. | Process for obtaining a metallurgical bond between a metal material, or a composite material having a metal matrix, and a metal casting or a metal-alloy casting |
-
1990
- 1990-06-19 FR FR9007667A patent/FR2663250A1/en active Granted
-
1991
- 1991-05-17 EP EP19910401295 patent/EP0462850B1/en not_active Expired - Lifetime
- 1991-05-17 DE DE1991630038 patent/DE69130038T2/en not_active Expired - Fee Related
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2439870A1 (en) * | 1973-08-20 | 1975-03-06 | Ford Werke Ag | COMPOSITION ROTOR HOUSING WITH WEAT-RESISTANT COATING |
EP0203198A1 (en) * | 1984-11-07 | 1986-12-03 | Mitsubishi Jidosha Kogyo Kabushiki Kaisha | Method of reinforcing a metallic article |
GB2173436A (en) * | 1985-03-29 | 1986-10-15 | Kolbenschmidt Ag | Composite casting process |
EP0246423A2 (en) * | 1986-05-23 | 1987-11-25 | Vereinigte Aluminium-Werke Aktiengesellschaft | Method of and installation for resistant connection of ceramic mould parts with metals |
WO1989009669A1 (en) * | 1988-04-15 | 1989-10-19 | Sandvik Australia Pty. Limited | Composite hard metal-metal components |
EP0384045A2 (en) * | 1989-02-22 | 1990-08-29 | TEMAV S.p.A. | Process for obtaining a metallurgical bond between a metal material, or a composite material having a metal matrix, and a metal casting or a metal-alloy casting |
Non-Patent Citations (1)
Title |
---|
"Metals Handbook", édition 9, vol. 5: "Surface cleaning, finishing and coating", 1982, pages 601-606, ASM, Ohio, US; "Surface preparation methods (for aluminium) * |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2736968A1 (en) * | 1995-07-18 | 1997-01-24 | Renault | Housing area for valve seats in IC engine cylinder head - has thermal screen fitted over landing area between adjacent valve seat housings, with screen held in place by side panels, fitting between valve seat housings |
WO2004018718A1 (en) * | 2002-08-20 | 2004-03-04 | 3M Innovative Properties Company | Metal matrix composites, and methods for making the same |
EP1460151A1 (en) * | 2003-03-19 | 2004-09-22 | Ford Global Technologies, LLC, A subsidary of Ford Motor Company | Cylinder head for reciprocating internal combustion engines |
WO2006023080A1 (en) * | 2004-07-29 | 2006-03-02 | 3M Innovative Properties Company | Metal matrix composites, and methods for making the same |
WO2006023069A1 (en) * | 2004-07-29 | 2006-03-02 | 3M Innovative Properties Company | Metal matrix composites, and methods for making the same |
WO2006023070A1 (en) * | 2004-07-29 | 2006-03-02 | 3M Innovative Properties Company | Metal matrix composites, and methods for making the same |
WO2007137314A2 (en) | 2006-05-26 | 2007-12-06 | Avl List Gmbh | Cylinder head for an internal combustion engine |
AT502971B1 (en) * | 2006-12-07 | 2008-05-15 | Avl List Gmbh | CYLINDER HEAD FOR AN INTERNAL COMBUSTION ENGINE |
CN114645796A (en) * | 2022-01-13 | 2022-06-21 | 爱柯迪股份有限公司 | Silicon nitride fiber reinforced aluminum alloy engine cylinder sleeve and preparation method thereof |
CN114645796B (en) * | 2022-01-13 | 2023-03-03 | 爱柯迪股份有限公司 | Silicon nitride fiber reinforced aluminum alloy engine cylinder sleeve and preparation method thereof |
Also Published As
Publication number | Publication date |
---|---|
FR2663250A1 (en) | 1991-12-20 |
DE69130038D1 (en) | 1998-10-01 |
EP0462850B1 (en) | 1998-08-26 |
FR2663250B1 (en) | 1994-12-30 |
DE69130038T2 (en) | 1999-05-12 |
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