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EP0276593A1 - Method of making cast metallic pieces containing a ceramic insert - Google Patents

Method of making cast metallic pieces containing a ceramic insert Download PDF

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Publication number
EP0276593A1
EP0276593A1 EP87402809A EP87402809A EP0276593A1 EP 0276593 A1 EP0276593 A1 EP 0276593A1 EP 87402809 A EP87402809 A EP 87402809A EP 87402809 A EP87402809 A EP 87402809A EP 0276593 A1 EP0276593 A1 EP 0276593A1
Authority
EP
European Patent Office
Prior art keywords
insert
metal
ceramic
electro
deposition
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP87402809A
Other languages
German (de)
French (fr)
Other versions
EP0276593B1 (en
Inventor
Daniel Gapin
Christian Jouin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Automobiles Peugeot SA
Automobiles Citroen SA
Original Assignee
Automobiles Peugeot SA
Automobiles Citroen SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Automobiles Peugeot SA, Automobiles Citroen SA filed Critical Automobiles Peugeot SA
Publication of EP0276593A1 publication Critical patent/EP0276593A1/en
Application granted granted Critical
Publication of EP0276593B1 publication Critical patent/EP0276593B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • 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
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D13/00—Electrophoretic coating characterised by the process
    • C25D13/02—Electrophoretic coating characterised by the process with inorganic material

Definitions

  • the present invention relates to a method for manufacturing cast metal parts, in particular of light alloy comprising an insert of ceramic material.
  • the insert can for example function as an internal coating on parts such as pipes or exhaust manifolds in order to thermally insulate them.
  • the parts thus obtained combine the properties of mechanical strength, lightness and thermal insulation.
  • the method according to the invention aims to remedy these difficulties.
  • This process is characterized in that, before the casting of the metal, a flexible mattress of ceramic fibers is deposited on the insert by electro-deposition, for example by anaphoresis.
  • a metal part 1 comprising an insert 2 of ceramic material
  • the insert is made to the desired shape, a flexible mattress 3 of fibers of ceramic material is deposited on this insert, and a mold 4 is placed in a mold. the insert thus coated and the metal 1 is poured into the mold ( Figure 2).
  • the insert 2 is made electrically conductive by a metallic deposit 5 in a thin layer, this deposit being effected by means of a plasma, a paint or a varnish, the insert with its deposit is immersed in a bath 6 made up of ceramic fibers and colloidal silica suspended in water, and the metal deposit 5 is connected to the positive pole of a voltage source of which the negative pole is connected to one electrode 7 immersed in suspension 6; the ceramic fibers of the suspension are thus deposited by anaphoresis on the insert 2 to form the fiber mat 3.
  • the colloidal silica in suspension 6 has a triple role: - modify the pH of the suspension to make it electrically conductive. - entrain the fibers towards the surface of the part 2 to be coated. - Ensure the cohesion of the fibers between them on the surface of part 2 and bind the deposit to the surface of the part (role of cement, silica depositing in the form of gel).
  • the mattress 3 can be produced in a few minutes; for example in five to ten minutes, in the case of a mattress two millimeters thick.
  • the insert After formation of the mattress 3, the insert is dried in ambient air and then steamed to remove the excess water; high temperature heat treatment dehydrates the gel and sinter the silica.
  • the deformation power of the fibrous mat obtained 3 depends on the concentration of silica in the bath (percentage of silica / percentage of fibers deposited), that is to say the ratio between the percentage of silica and that of fibers deposited.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Or Physical Treatment Of Fibers (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)

Abstract

1. Method of manufacturing a cast metal part comprising a ceramic material insert (2), in which this insert is inserted in a mould (4) and then the metal (1) is cast in the mould, characterized in that, before casting the metal, a flexible mat (3) of ceramic material fibres is deposited on the insert (2) by electro-deposition in a bath (6) formed by a suspension of ceramic fibres and colloidal silica in water.

Description

La présente invention concerne un procédé pour fabri­quer des pièces métalliques coulées, notamment en alliage léger comportant un insert en matière cérami­que. L'insert peut par exemple faire fonction de revêtement interne sur des pièces telles que des tu­bulures ou collecteurs d'échappement afin de les isoler thermiquement.The present invention relates to a method for manufacturing cast metal parts, in particular of light alloy comprising an insert of ceramic material. The insert can for example function as an internal coating on parts such as pipes or exhaust manifolds in order to thermally insulate them.

Pour fabriquer de telles pièces, on commence jusqu'à présent par réaliser une pièce en matière céramique à la forme voulue et on l'insère dans le moule avant la coulée de manière à obtenir au démoulage une piè­ce métallique comportant un revêtement en céramique interne.To manufacture such parts, one begins so far by making a ceramic part in the desired shape and is inserted into the mold before casting so as to obtain the release of a metal part having an internal ceramic coating.

Les pièces ainsi obtenues cumulent les propriétés de tenue mécanique, de légéreté et d'isolement ther­mique.The parts thus obtained combine the properties of mechanical strength, lightness and thermal insulation.

Mais cette technique rencontre d'importantes diffi­cultés principalement pour les pièces de grandes di­mensions en raison des contraintes résiduelles in­duites par le retrait de l'alliage après solidifi­cation; il peut en résulter une destruction de l'in­sert en matière céramique.However, this technique encounters major difficulties mainly for large parts because of the residual stresses induced by the withdrawal of the alloy after solidification; this may result in destruction of the ceramic insert.

Le procédé selon l'invention a pour but de remédier à ces difficultés.The method according to the invention aims to remedy these difficulties.

Ce procédé est caractérisé en ce que, avant la cou­lée du métal, on dépose sur l'insert par électro-dé­position, par exemple par anaphorèse, un matelas souple de fibres en matière céramique.This process is characterized in that, before the casting of the metal, a flexible mattress of ceramic fibers is deposited on the insert by electro-deposition, for example by anaphoresis.

On a décrit ci-après, à titre d'exemple non limita­tif, un mode de mise en oeuvre du procédé selon l'in­vention, avec référence au dessin annexé dans lequel :

  • La Figure 1 est une vue en coupe d'une pièce métallique munie d'un insert céramique par le procédé selon l'invention;
  • La Figure 2 est une vue en coupe montrant l'insert en place dans un moule;
  • La Figure 3 est une vue en coupe montrant la réalisation du dépôt fibreux sur l'insert.
An embodiment of the method according to the invention has been described below, by way of nonlimiting example, with reference to the appended drawing in which:
  • Figure 1 is a sectional view of a metal part provided with a ceramic insert by the method according to the invention;
  • Figure 2 is a sectional view showing the insert in place in a mold;
  • Figure 3 is a sectional view showing the production of the fibrous deposit on the insert.

Selon l'invention, pour fabriquer une pièce métalli­que 1 comportant un insert 2 en matière céramique, on réalise l'insert à la forme voulue, on dépose sur cet insert un matelas souple 3 de fibres en ma­tière céramique, on place dans un moule 4 l'insert ainsi revêtu et on coule le métal 1 dans le moule (Figure 2).According to the invention, to manufacture a metal part 1 comprising an insert 2 of ceramic material, the insert is made to the desired shape, a flexible mattress 3 of fibers of ceramic material is deposited on this insert, and a mold 4 is placed in a mold. the insert thus coated and the metal 1 is poured into the mold (Figure 2).

Dans le mode de mise en oeuvre de la Figure 3, on rend l'insert 2 électriquement conducteur par un dépôt métallique 5 en couche mince, ce dépôt étant effectué au moyen d'un plasma, d'une peinture ou d'un vernis, on immerge l'insert avec son dépôt dans un bain 6 constitué de fibres céramique et de silice colloïdale en suspension dans de l'eau, et on connec­te le dépôt métallique 5 au pôle positif d'une source de tension dont le pôle négatif est connecté à une electrode 7 immergée dans la suspension 6; les fibres céramique de la suspension se déposent ainsi par ana­phorèse sur l'insert 2 pour former le matelas de fi­bres 3.In the embodiment of FIG. 3, the insert 2 is made electrically conductive by a metallic deposit 5 in a thin layer, this deposit being effected by means of a plasma, a paint or a varnish, the insert with its deposit is immersed in a bath 6 made up of ceramic fibers and colloidal silica suspended in water, and the metal deposit 5 is connected to the positive pole of a voltage source of which the negative pole is connected to one electrode 7 immersed in suspension 6; the ceramic fibers of the suspension are thus deposited by anaphoresis on the insert 2 to form the fiber mat 3.

La silice colloïdale de la suspension 6 a un triple rôle :
- modifier le pH de la suspension pour la rendre électriquement conductrice.
- entraîner les fibres vers la surface de la pièce 2 à revêtir.
- assurer à la surface de la pièce 2 la cohésion des fibres entre elles et lier le dépôt à la surface de la pièce (rôle de ciment, la silice se déposant sous la forme de gel).The colloidal silica in suspension 6 has a triple role:
- modify the pH of the suspension to make it electrically conductive.
- entrain the fibers towards the surface of the part 2 to be coated.
- Ensure the cohesion of the fibers between them on the surface of part 2 and bind the deposit to the surface of the part (role of cement, silica depositing in the form of gel).

Dans le cas d'un insert 2 de grandes dimensions ou de forme compliquée, on lui imprime de préférence un mouvement de rotation pour assurer une homogénéité du dépôt. Le matelas 3 peut être réalisé en quelques minutes; par exemple en cinq à dix minutes, dans le cas d'un matelas de deux millimètres d'épaisseur.In the case of an insert 2 of large dimensions or of complicated shape, it is preferably printed with a rotational movement to ensure uniformity of the deposit. The mattress 3 can be produced in a few minutes; for example in five to ten minutes, in the case of a mattress two millimeters thick.

Après formation du matelas 3, l'insert est séché à l'air ambiant puis étuvé pour retirer l'eau en excès; un traitement thermique à haute température déshydra­te le gel et fritte la silice.After formation of the mattress 3, the insert is dried in ambient air and then steamed to remove the excess water; high temperature heat treatment dehydrates the gel and sinter the silica.

Le pouvoir de déformation du matelas fibreux obtenu 3 dépend de la concentration en silice du bain (pour­centage de silice / pourcentage de fibres déposées) c'est-à-dire du rapport entre le pourcentage de sili­ce et celui de fibres déposées.The deformation power of the fibrous mat obtained 3 depends on the concentration of silica in the bath (percentage of silica / percentage of fibers deposited), that is to say the ratio between the percentage of silica and that of fibers deposited.

Le procédé qui vient d'être décrit présente de nom­breux avantages :

  • 1) dépôt possédant une souplesse (déformation) cons­tante et une porosité contrôlée.
  • 2) dépôt constant dans l'épaisseur.
  • 3) possibilité de faire des dépôts d'épaisseur contrô­lée.
  • 4) temps de dépôt très court.
  • 5) ensemble très réfractaire.
  • 6) très forte cohésion entre le dépôt (matelas 3) fibreux et la céramique massive 2.
  • 7) bon accrochage du métal 1 sur l'ensemble de l'in­sert lors de l'insertion à la coulée dans un al­liage léger, sans apparition de bulles ou de refus de métal.
  • 8) possibilité de dépôt sur des formes complexes.
The process which has just been described has many advantages:
  • 1) deposit having constant flexibility (deformation) and controlled porosity.
  • 2) constant deposit in thickness.
  • 3) possibility of making deposits of controlled thickness.
  • 4) very short deposit time.
  • 5) very refractory.
  • 6) very strong cohesion between the fibrous deposit (mattress 3) and the massive ceramic 2.
  • 7) good attachment of metal 1 to the entire insert during insertion into the casting in a light alloy, without the appearance of bubbles or metal refusal.
  • 8) possibility of filing on complex shapes.

Il va de soi que la présente invention ne doit pas être considérée comme limitée au mode de mise en oeuvre décrit et représenté, mais en couvre, au contraire, toutes les variantes.It goes without saying that the present invention should not be considered as limited to the embodiment described and shown, but on the contrary covers all variants thereof.

Claims (5)

1. Procédé de fabrication d'une pièce coulée compor­tant un insert (2) en matière céramique, dans lequel on place cet insert dans un moule (4), et on coule ensuite le métal (1) dans le moule,
caractérisé en ce que, avant la coulée du métal,on dépose sur l'insert (2) par électro-déposition, par exemple par anaphorèse, un matelas souple (3) de fi­bres en matière céramique.1. Method for manufacturing a casting comprising an insert (2) made of ceramic material, in which this insert is placed in a mold (4), and the metal (1) is then poured into the mold,
characterized in that, before the metal is poured, a flexible mattress (3) of ceramic fibers is deposited on the insert (2) by electro-deposition, for example by anaphoresis. 2. Procédé selon la revendication 1,
caractérisé en ce qu'avant l'électro-déposition on revêt l'insert (2) d'un dépôt métallique en couche mince (5), au moyen d'un plasma, d'une peinture ou d'un vernis.2. Method according to claim 1,
characterized in that before the electrodeposition the insert (2) is coated with a metallic deposit in a thin layer (5), by means of a plasma, a paint or a varnish. 3. Procédé selon la revendication 1 ou 2,
caractérisé en ce qu'on procède à l'électro-déposition dans un bain (6) constitué par une suspension de fibres céramique et de silice colloïdale dans de l'eau.3. Method according to claim 1 or 2,
characterized in that the electro-deposition is carried out in a bath (6) consisting of a suspension of ceramic fibers and colloidal silica in water. 4. Procédé selon la revendication 3,
caractérisé en ce qu'on imprime un mouvement de rota­tion à l'insert (2), pendant l'électro-déposition.4. Method according to claim 3,
characterized in that a rotary movement is imparted to the insert (2), during the electrodeposition. 5. Procédé selon la revendication 3 ou 4, caractérisé en ce qu'après l'électro-déposition on sèche l'insert à l'air ambiant, on l'étuve et on le porte à une tem­pérature propre à déshydrater et à fritter la silice.5. Method according to claim 3 or 4, characterized in that after the electro-deposition the insert is dried in ambient air, it is steamed and it is brought to a temperature suitable for dehydrating and sintering the silica.
EP19870402809 1986-12-18 1987-12-11 Method of making cast metallic pieces containing a ceramic insert Expired - Lifetime EP0276593B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8618129A FR2608476B1 (en) 1986-12-18 1986-12-18 PROCESS FOR MANUFACTURING CAST METAL PARTS INCLUDING A CERAMIC INSERT
FR8618129 1986-12-18

Publications (2)

Publication Number Publication Date
EP0276593A1 true EP0276593A1 (en) 1988-08-03
EP0276593B1 EP0276593B1 (en) 1990-02-07

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EP19870402809 Expired - Lifetime EP0276593B1 (en) 1986-12-18 1987-12-11 Method of making cast metallic pieces containing a ceramic insert

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EP (1) EP0276593B1 (en)
DE (1) DE3761614D1 (en)
FR (1) FR2608476B1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0440093A1 (en) * 1990-01-26 1991-08-07 Isuzu Motors Limited Cast product having ceramics as insert and method of making same
DE19814018A1 (en) * 1998-03-28 1999-09-30 Andreas Roosen Ceramic-polymer, ceramic-ceramic or ceramic-metal composite, e.g. a piezoceramic-polymer composite for an ultrasonic transducer
US10493677B2 (en) * 2014-11-21 2019-12-03 Solvay Specialty Polymers Usa, Llc Overmolded inserts and methods for forming the same
EP4166257A1 (en) * 2021-10-13 2023-04-19 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Composite casting method with deformation of an insert part for preventing tear or breaks between cast metal and insert part, and composite component

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1228449B (en) * 1989-02-22 1991-06-19 Temav Spa PROCEDURE FOR OBTAINING A METALLURGICAL BOND BETWEEN A METALLIC MATERIAL OR COMPOSITE WITH METALLIC MATRIX AND A CAST OF METAL OR METAL ALLOY.
US5616421A (en) * 1991-04-08 1997-04-01 Aluminum Company Of America Metal matrix composites containing electrical insulators

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB860290A (en) * 1957-07-19 1961-02-01 Platecraft Of America Inc Electroformed article and a method of making the same
DE2430753A1 (en) * 1973-07-31 1975-02-13 Nissan Motor METHOD OF APPLYING A GAMMA ALUMINUM OXYD COATING TO THE SURFACE OF A FIREPROOF MOLDED BODY
US3966576A (en) * 1974-07-15 1976-06-29 Ppg Industries, Inc. Electrophoretic deposition of asbestos diaphragms
US4318438A (en) * 1977-09-27 1982-03-09 Honda Giken Kogyo Kabushiki Kaisha Method for casting a fiber-reinforced composite article

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5964150A (en) * 1982-10-06 1984-04-12 Toyota Motor Corp Joining method of ceramic and metal
JPS60240366A (en) * 1984-05-15 1985-11-29 Toyota Motor Corp Insert-casting method of ceramic body

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB860290A (en) * 1957-07-19 1961-02-01 Platecraft Of America Inc Electroformed article and a method of making the same
DE2430753A1 (en) * 1973-07-31 1975-02-13 Nissan Motor METHOD OF APPLYING A GAMMA ALUMINUM OXYD COATING TO THE SURFACE OF A FIREPROOF MOLDED BODY
US3966576A (en) * 1974-07-15 1976-06-29 Ppg Industries, Inc. Electrophoretic deposition of asbestos diaphragms
US4318438A (en) * 1977-09-27 1982-03-09 Honda Giken Kogyo Kabushiki Kaisha Method for casting a fiber-reinforced composite article

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, vol. 10, no. 109 (M-472), 23 avril 1986; & JP-A-60 240 366 (TOYOTA JIDOSHA K.K.) 29-11-1985 *
PATENT ABSTRACTS OF JAPAN, vol. 11, no. 184 (C-427)[2631], 12 juin 1987; & JP-A-62 004 844 (TOSHIBA CORP.) 10-01-1987 *
PATENT ABSTRACTS OF JAPAN, vol. 8, no. 170 (M-315), 7 août 1984; & JP-A-59 064 150 (TOYOTA JIDOSHA K.K.) 12-04-1984 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0440093A1 (en) * 1990-01-26 1991-08-07 Isuzu Motors Limited Cast product having ceramics as insert and method of making same
DE19814018A1 (en) * 1998-03-28 1999-09-30 Andreas Roosen Ceramic-polymer, ceramic-ceramic or ceramic-metal composite, e.g. a piezoceramic-polymer composite for an ultrasonic transducer
US10493677B2 (en) * 2014-11-21 2019-12-03 Solvay Specialty Polymers Usa, Llc Overmolded inserts and methods for forming the same
EP4166257A1 (en) * 2021-10-13 2023-04-19 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Composite casting method with deformation of an insert part for preventing tear or breaks between cast metal and insert part, and composite component

Also Published As

Publication number Publication date
FR2608476A1 (en) 1988-06-24
DE3761614D1 (en) 1990-03-15
EP0276593B1 (en) 1990-02-07
FR2608476B1 (en) 1989-05-12

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