JP3452822B2 - Manufacturing method of aluminum-ceramic composite member - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a method for manufacturing a ceramic composite member,
In particular, the present invention relates to an industrial method for producing a composite material of oxide, nitride, or carbide ceramics and aluminum, which is suitable for automobile parts, electronic parts, and the like.

[0002]

2. Description of the Related Art Metal-ceramics composite members that take advantage of the characteristics of ceramics such as chemical stability, high melting point, insulation, and hardness and the characteristics of metals such as high strength, high toughness, workability, and conductivity are known. Widely used in automobiles, electronic devices, etc. Typical examples thereof include rotors for automobile turbochargers, substrates and packages for mounting high-power electronic devices.

As a method of manufacturing a metal-ceramic composite member, adhesion, plating, metallization, thermal spraying, brazing, DB
Methods such as C, shrink fitting, and cast molding are known. The bonding method is a method of bonding a metal member and a ceramic member with an organic or inorganic adhesive. The plating method is a method of activating the surface of a ceramic member and then putting it in a plating solution to perform metal plating. The metallizing method is a method of forming a metal layer by applying a paste containing metal powder on the surface of a ceramic member and then sintering the paste. The thermal spraying method is a method in which droplets of a metal (ceramic) are jetted onto the surface of a ceramic (metal) member to form a metal (ceramic) layer on the surface of the ceramic (metal) member. The brazing method is a method of joining a metal member and a ceramic member with a metal or alloy (brazing material) having a low melting point interposed therebetween. In order to firmly bond the brazing material to the ceramic member, the brazing material reacts with the ceramic. A metal component that is easy to add is added, or a metal layer is formed on the bonding surface of the ceramic member in advance by a method such as the above-described metallization or thermal spraying. The DBC method is
This is a technology developed for bonding oxide ceramic members and copper members.When bonding, the copper containing oxygen is heated in an inert atmosphere, or the surface of an oxygen-free copper plate is pre-oxidized and then oxidized. It is a method of joining after forming a physical layer.
When joining a non-oxide ceramic member and a copper member by this method, it is necessary to previously form an oxide layer on the surface of the non-oxide member. In the case of shrink fitting, the ceramic and metal members to be joined are each provided with a convex portion and a concave portion, the outer diameter of the convex portion and the inner diameter of the concave portion are set to the same size, and the inner diameter of the concave portion provided by heating the metal member at the time of joining is enlarged. Then, by inserting the convex portion of the ceramic member into the convex portion and then cooling the concave portion, the concave portion of the metal is integrated with the convex portion of the ceramic. The cast stuffing method is a method similar to the shrink fitting method, in which a metal is cast around the ceramic component and the ceramic component is wrapped by the cooling shrinkage of the metal to be integrated.

However, in such a conventional technique,
In the case of the bonding method, there are problems that the bonding strength is low and the heat resistance is poor. In the case of plating, metallizing, or thermal spraying, the formed metal (ceramic) is limited to a thin layer having a thickness of several μm to several tens of μm. Shrink-fit and cast-mold methods are limited to the particular case where at least a portion of the ceramic member is embraced by the metal. In the DBC method, the metal that can be bonded is limited to copper, and the bonding temperature is C
Since it is limited to a narrow range near the eutectic point of u—O, there is a problem that swelling and non-contact bonding defects are likely to occur. In the case of the brazing method, since an expensive brazing material is used and the joining has to be performed in a vacuum, the cost is very high and the application range is limited. Also, eutectic alloys containing metals to be joined, other metals, and even non-metals are generally used as the brazing material, and since it is harder than the metals to be joined in general, the brazing material However, there are problems such as short heat cycle life.

[0005]

As described above, when the metal member and the ceramic member are joined by the conventional technique, there is one of the following problems. 1) Metal and ceramic members to be joined are limited to those having a specific shape. 2) The cost of the joining process is high and the range of applications is limited. 3) The characteristics (bonding strength, heat resistance, heat cycle resistance) of the bonded body have not been achieved to the extent that the required characteristics can be satisfied.

Therefore, the present invention was carried out to solve the above-mentioned problems, and specifically, the present invention provides ceramic-aluminum composite members having various shapes having excellent characteristics at low cost. The purpose is to provide a method for mass production.

[0007]

Means for Solving the Problems The inventors of the present invention have made extensive studies in order to solve the above problems, and have found a method for joining a molten aluminum and ceramics and a method for forming aluminum, and can make the present invention. It was

That is, the present invention is, firstly, in the production of an aluminum-ceramic composite member 5 in which aluminum is joined to one surface or both surfaces of a ceramic plate material,
A reaction system is set in an inert gas atmosphere, the surface of the ceramic plate is moved in direct contact with the molten aluminum 1 and, after being wetted with the molten metal, cooled through a die having a predetermined hole shape. Second, a method for producing an aluminum-ceramic composite member 5, characterized in that the molten metal is solidified on the surface of the ceramic plate material and an aluminum body having a predetermined cross-sectional shape is joined with a peel strength larger than 35 kg / cm; In the production of the aluminum-ceramic composite member 5 in which aluminum is joined to one or both sides of the ceramic plate material, the molten metal of aluminum in which the reaction system is set in an inert gas atmosphere and the surface of the ceramic plate material is pressed. After moving the ceramic plate in the state of being in direct contact with No. 1 and wetting it with the molten aluminum 1 Aluminum characterized in that the molten aluminum 1 is solidified on the surface of the ceramic plate material through a die having a predetermined hole shape to prevent formation of cavities and form an aluminum body having a predetermined cross-sectional shape having a peel strength of more than 35 kg / cm. -Manufacturing method of the ceramics composite member 5: Thirdly, in the manufacture of the aluminum-ceramics composite member 5 in which aluminum is bonded to the opposite surface of the ceramics plate material having one surface previously bonded with metal, the reaction system is inactive The ceramic plate material is continuously supplied to the aluminum melt 1 under pressure in a gas atmosphere, and the ceramic plate material is moved with the opposite surface of the ceramic plate material being in contact with the aluminum melt 1. After the aluminum melt 1 is wetted, the aluminum alloy is applied to the opposite surface through a die having a predetermined hole shape. The beam melt 1 is solidified, the peel strength to prevent the occurrence of nests 35 kg / cm
A method for manufacturing an aluminum-ceramic composite member 5, characterized by taking out the above-mentioned ceramic plate material on which an aluminum body having a larger predetermined cross-sectional shape is formed;
The above-mentioned ceramic plate material moves in the above-mentioned molten aluminum while being held at its side edges.
5. The method for producing the aluminum-ceramic composite member 5 according to any one of 3 to 5; 5th, the aluminum-ceramic composite member according to any of 1 to 4, wherein the ceramic plate material is an oxide, a nitride, or a carbide. 5 is related to the manufacturing method.

[0009]

[Function] Joining of metal and ceramics is classified into mechanical joining (hereinafter mechanical joining), physical joining (hereinafter physical joining), and chemical joining (hereinafter chemical joining) depending on the joining mechanism. The mechanical joining is a joining in which the convex portion of the ceramic is held by a mechanical force in the concave portion of the metal such as the case of the above-mentioned shrink fitting and the casting method, or the surface of the ceramic and the metal member such as the bonding method. The adhesive enters into the concave portion of and the joining is such that the metal and the ceramic are integrated by the anchor effect of the cured adhesive. Physical bonding refers to the case of bonding by a suction force (van der Waals force) between a ceramic molecule and a metal atom. Chemical joining refers to joining or sharing between electrons inside a ceramic molecule and electrons inside a metal atom, that is, joining by covalent or ionic bonding. For chemical bonding,
A reaction product that is physically discoverable (for example, by conventional optical microscope, scanning electron microscope, transmission electron microscope observation) because it is established if there is electron sharing or interaction between ceramics and metal surface molecules (atoms). Does not always exist at the interface. In that case, it is often not possible to distinguish from the state of the interface whether it is physically bonded or chemically bonded. In practice, several bonding mechanisms are often present at the interface of the bonded body at the same time, but in order to realize highly reliable bonding, it is necessary to achieve physical bonding or chemical bonding.

Whether physical bonding or chemical bonding has occurred is often judged from the wetting condition. In general, droplets spread when placed on a solid and equilibrate over a period of time. The angle between the tangential line of the liquid, the solid, and the contact point (line) of the atmosphere at equilibrium and the surface of the solid, that is, the contact angle, is measured, and this is used. Shows the wetting status of liquid to solid. The contact angle is generally small when physical and chemical bonding occurs. In the present invention, a simpler and more practical method described below was used to examine the wetting condition. That is, the ceramic member 2 is brought into contact with the aluminum melt 1 heated to a constant temperature, and after a certain time elapses, the melt 1
The ceramic member 2 is taken out from. The aluminum remaining on the cooled surface of the ceramic member 2 is scratched with a knife or the like to remove the floating aluminum portion, and the wet state of the ceramic member 2 with aluminum is examined.

In order to achieve physical and chemical bonding, the surfaces of the parts to be bonded must first be cleaned. For example, as disclosed by one of the inventors in another invention (Reference 1, Japanese Patent Application No. 4-355211), a chemically active metal, typified by aluminum, is exposed to air when it is placed in air. It was found that the surface was oxidized and the effect was that metal had lost its original activity and could not be joined firmly to ceramics. As is well known to those skilled in the art, a strong bonded body cannot be obtained unless the surface of the bonded member is degreased before the bonding work to remove oil and fat on the surface of the bonded member.

One of the inventors has devised a method of cleaning the surfaces of the members to be joined in the above invention (reference document 1, Japanese Patent Application No. 4-355511). That is, by inserting the ceramic member 2 into the molten metal 1 or casting the molten metal 1 into the set ceramic member 2, relative motion is generated between the molten metal 1 and the ceramic member 2. , The interface between the molten metal and the member is cleaned, and the metal is firmly bonded to the member. The inventors of the present invention made further efforts based on the above-mentioned invention to find out an industrial manufacturing method of the aluminum-ceramic composite member 5. That is, (1) when the ceramic member 2 is inserted into the molten aluminum 1, the ceramic member 2 is moved in the molten aluminum 1 until at least the portion of the ceramic member 2 to be joined to aluminum gets wet with the molten aluminum 1, ( 2) When the ceramic member 2 is taken out from the molten aluminum 1, a part of the molten aluminum 1 is solidified in a predetermined shape on the ceramic member 2 through a die 6 processed into a fixed shape. It is a method of manufacturing the aluminum-ceramics composite member 5.

It must be emphasized here that cleaning the surface does not necessarily mean the removal of all but the component components. Rather, if the component has an effect of promoting physical or chemical bonding, that effect should be positively utilized. For example, the above DB
As in the case of C, when the presence of oxides on the surfaces of the joined members is a prerequisite for achieving strong joining, the surfaces of the joined members are previously oxidized to form an oxide layer. There is a need. The meaning of cleaning in the present invention is nothing more than removing components that impede the achievement of physical and chemical bonding.

FIG. 2 is a schematic diagram for explaining the principle of the present invention. As shown in this figure, when the movement distance of the ceramic member 2 in the molten aluminum is short, the contact between the molten aluminum 1 and the ceramic member 2 becomes insufficient, and the harmful component 4 on the surface of the ceramic member is reduced.
Also, the harmful component 3 on the surface of the molten aluminum cannot be removed sufficiently, and therefore, the molten aluminum 1 is not sufficiently wetted to a part of the ceramic member 2, and a strong joint cannot be achieved. In order to prevent such a bonding failure, the distance that the ceramic member 2 moves in the molten aluminum 1 must exceed a certain minimum distance (Dmin).
This shortest distance depends on the characteristics of the molten aluminum 1 and the ceramic member 2, the state of harmful components existing on their surfaces,
In the case of the embodiment of the present invention, this shortest distance is several mm to several tens of mm, although it varies depending on the temperature, the atmosphere, the moving speed of the ceramic member 2, and the like.

Example 1 of the present invention discloses an example of a method for manufacturing the aluminum-ceramic composite member 5.
FIG. 1 shows a schematic cross-sectional view of the manufacturing apparatus, and FIG. 3 shows a cross-sectional view of the outlet side of the mold (die) 6. Ceramics member 2
Of the mold (die) 6 continuously enters the inside of the molten metal from one side and is sufficiently wet before the mold (die) 6 in the opposite direction.
And an aluminum body having a predetermined shape is formed at a predetermined place on the ceramic member 2. In this case, if the size of the molten metal in the moving direction of the ceramic member 2 is made longer than the shortest distance until the ceramic member 2 gets wet, a sound aluminum-ceramic composite member 5 can be manufactured.

The above-mentioned embodiments are merely examples for explaining the essential points of the present invention, and the method shown in the embodiments is obviously one of the manufacturing steps for achieving the object of the present invention. However, it will be readily understood that the present invention is not limited to only the method disclosed in this example. Even if the aluminum itself does not directly wet the ceramic member 2, the surface of the ceramic member 2 may be modified, or a component that promotes wetting may be added to the aluminum to form the ceramic member 2 and the molten aluminum 1. Methods to improve wetting can be applied as well. For example, when manufacturing a composite member of copper and aluminum nitride, in order to improve the wetting of the aluminum and aluminum nitride member,
The surface of ceramics is pre-oxidized to form oxides such as alumina on the surface, or molten aluminum 1
The wetness of the molten aluminum and the ceramic member 2 can be improved and the ceramic member 2 and the aluminum body can be strongly bonded by exposing the steel to the air or adding oxygen by adding copper oxide or the like. It is possible.

In the case of the present invention, needless to say, the temperature, the atmosphere, and the moving speed of the ceramic member 2 are very important parameters, but since the characteristics of the various ceramic members 2 are different, these parameters depend on the members to be joined. change. These conditions may be selected so that the molten aluminum 1 and the ceramic member 2 get wet. Selection of these conditions is an important measure for maximizing the effect of the present invention. However, the following points should be noted when selecting these conditions. That is, in the method of the present invention, wetting itself is a key point for producing the aluminum-ceramic composite member 5, and raising the temperature of the molten metal to extend the contact time is effective in improving wetting, but is necessary. When the temperature of the molten metal is increased or the contact time is increased as described above, a thick reaction product is formed at the interface between the aluminum member and the ceramic member 2, and the bonding strength may be reduced.

[0018]

Example 1 FIG. 1 shows a schematic sectional view of a manufacturing apparatus, and FIG.
A sectional view of the outlet side mold (die) 6B is shown in FIG. Aluminum is set in the crucible 7, an alumina plate is put in from the entrance of the die 6, and the tip is set so as to slightly protrude from the inner wall of the crucible 7. Then, the crucible 7 is put in a nitrogen gas (N ₂ ) atmosphere. Heat to melt aluminum. The molten aluminum enters the die 6B on the outlet side, but the temperature of the tip portion drops below the melting point while flowing through the die,
The part solidifies and blocks the outlet, preventing the molten metal from flowing out. Further, in order to prevent the molten metal from entering the die 6A on the inlet side and the gap between the die and the crucible 7, the clearance must be set to a certain dimension or less. Was set to 0.1 mm or less. After the aluminum melt is heated to a certain set temperature,
Alumina plate is continuously supplied from the inlet side. The alumina plate material sequentially enters the molten metal, enters the die 6B on the outlet side after being wet with the molten metal, and finally, the aluminum plate having a thickness of 0.5 mm is joined to both surfaces of the alumina plate material, and the outlet is formed. Continuously extruded from. In this Example, the heating temperature, the extrusion temperature, and the flow rate of nitrogen gas were variously changed, and the shortest distance Dmin of moving the aluminum plate material in the molten aluminum until it was wet was measured, and an aluminum-alumina composite sheet material was manufactured. . A sample was cut out from the obtained composite plate material, and the composite plate material was examined by the evaluation method described in the previous invention (Reference Document 1, Japanese Patent Application No. 4-355511). The Dmin was obtained by removing the molten metal from the crucible 7 and then taking out the alumina plate material, and measuring the distance between the starting point of contact with the molten aluminum and the completely wetted portion. The results are summarized in Table 1.
From these results, the aluminum structure was dense and the peel strength was more than 35 kg / cm for all the samples except the sample of production number E. A good quality aluminum-alumina composite plate material could be produced by the method of the present invention.

[0019]

[Table 1]

[0020]

[Embodiment 2] In Embodiment 1, the inside of the die outlet side 6B is processed into a shape as shown in the sectional view of FIG.
Extrusion speed and nitrogen gas flow rate are 850 ° C and 25, respectively.
mm / min and 30 L / min, and to improve the bathing of the melt and to prevent the formation of cavities, 0.5
A good quality aluminum-alumina composite plate material having the radiation fins 10 on one surface could be manufactured by substantially the same method as in Example 1 except that the pressure of kg / cm ² was applied.

[0021]

[Example 3] In Example 2, an alumina plate was used in which a copper plate was previously bonded on one side by the DBC method, and when the copper plate-bonded alumina plate passed through the molten metal part, the copper plate was exposed to molten aluminum. In order to prevent this, the die 6 in the molten metal is processed into a shape as shown in the sectional view of FIG. 5 in substantially the same manner as in Example 2 with a copper plate on one side and an aluminum radiating fin 10 on one side. It has been possible to produce a good quality composite material having.

[0022]

According to the method of the present invention, a good quality aluminum-ceramic composite member 5 having various shapes can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an apparatus for producing an aluminum-ceramic composite member in an example of the present invention.

FIG. 2 is a schematic diagram for explaining the principle of the present invention.

FIG. 3 is a cross-sectional view on the outlet side of a die for manufacturing an aluminum-ceramics composite member in Example 1 of the present invention.

FIG. 4 is a cross-sectional view on the outlet side of a die for producing an aluminum-ceramics composite member in Example 2 of the present invention.

FIG. 5 is a cross-sectional view of a portion of a die for producing an aluminum-ceramic composite member according to a third embodiment of the present invention, the portion being located in a crucible.

[Explanation of symbols]

1: molten aluminum 2: Ceramic parts 3: Harmful components on the surface of molten aluminum 4: Hazardous components on the surface of ceramic members 5: Aluminum-ceramics composite member 6: Mold (die) 6A: mold (die) entrance side 6B: Mold (die) exit side 7: crucible 8: Heater 9: Joined metal 10: Aluminum radiation fin Arrow →: Ceramic member movement direction

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshikazu Tanaka 1-8-2 Marunouchi, Chiyoda-ku, Tokyo Dowa Mining Co., Ltd. (56) Reference JP-A-59-227789 (JP, A) JP-A-63 -317245 (JP, A) JP-A 1-2202356 (JP, A) JP-A 7-193358 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C04B 37/02 B22D 19/00

Claims (5)

(57) [Claims] 1. In the production of an aluminum-ceramic composite member 5 in which aluminum is joined to one side or both sides of a ceramic plate material, the reaction system is set in an inert gas atmosphere, and the surface of the ceramic plate material is melted with the molten aluminum. 1 in a state of being in direct contact with the molten metal, wetted with the molten metal, and then cooled through a die having a predetermined hole shape to solidify the molten metal on the surface of the ceramic plate material ,
Aluminum body with a predetermined cross section is larger than 35 kg / cm
A method for manufacturing an aluminum-ceramics composite member 5, which is characterized in that bonding is performed with a threshold peel strength . 2. In the production of an aluminum-ceramic composite member 5 in which aluminum is joined to one or both sides of a ceramic plate material, the reaction system is set in an inert gas atmosphere and pressure is applied to the surface of the ceramic plate material. The ceramic plate is moved in a state of being in direct contact with the molten aluminum 1 and wetted with the molten aluminum 1 and then the molten aluminum 1 is solidified on the surface of the ceramic plate through a die having a predetermined hole shape, A method for producing an aluminum-ceramic composite member 5, which comprises forming an aluminum body having a predetermined cross-sectional shape that prevents the formation of cavities and has a peel strength of more than 35 kg / cm . 3. In the manufacture of an aluminum-ceramic composite member 5 in which a metal is bonded to one surface in advance of a ceramic plate material and aluminum is bonded to the opposite surface of the ceramic plate material,
With the reaction system set in an inert gas atmosphere, the ceramic plate material is continuously supplied to the aluminum melt 1 under pressure, and the opposite surface of the ceramic plate material is in contact with the aluminum melt 1 After moving the ceramic plate material and wetting it with the aluminum melt 1, the aluminum melt 1 is solidified on the opposite surface through a die having a predetermined hole shape to prevent formation of cavities and a peel strength of 35 kg / cm.
A method for manufacturing an aluminum-ceramic composite member 5, comprising taking out the above-mentioned ceramic plate material on which an aluminum body having a larger predetermined cross-sectional shape is formed. 4. The method for producing an aluminum-ceramic composite member 5 according to claim 1, wherein the ceramic plate material is moved in the molten aluminum while holding its side end portion. . Wherein said ceramic plate is an oxide, Ru nitride or carbide der, aluminum according to claim 1 - method of manufacturing a ceramic composite member 5.