JPH111732A - Manufacture of metal-ceramics composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in the conventional method of manufacture of a metal-ceramics composite that a composite material, e.g. a bolt after the completion of penetration of metal sinks and embeds itself into the residual molten metal and resultantly becomes difficult to be separated and taken out from the molten metal. SOLUTION: In this manufacturing method for a metal-ceramics composite material, a preform is prepared by using ceramic fibers or grains as reinforcement and a metal as a matrix material is allowed to penetrate into the preform. At this time, the penetration of the metal is carried out by previously inserting a dummy preform between the metal and the preform and then permitting the alloy composed essentially of aluminum to penetrate, via this dummy preform, into the preform at 700 to 1000 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a metal-ceramic composite material in which a metal is combined with a reinforcing material, and more particularly to a method for producing a metal-ceramic composite material which can be easily separated from the remaining metal.

[0002]

2. Description of the Related Art A metal-ceramic composite material reinforced with ceramic fibers or particles has both characteristics of a metal and a ceramic. For example, this composite material has high rigidity, low thermal expansion, abrasion resistance and the like. The ceramics have excellent characteristics such as ductility, high toughness, and high thermal conductivity. As described above, since it has both the characteristics of ceramics and metal, which have been considered difficult, it has been drawing attention as a next-generation material from industries such as mechanical device manufacturers.

As a method for producing this composite material, particularly a composite material using aluminum as a matrix as a metal, methods such as powder metallurgy, high pressure casting, and vacuum casting have been conventionally known. However, all of these methods are not capable of increasing the content of ceramics as a reinforcing material, require a large-sized pressurizing device, are difficult to form near nets, and are extremely expensive. It was not satisfactory.

Accordingly, recently, a non-pressurized metal infiltration method developed by Rankside Company of the United States has attracted particular attention as a manufacturing method for solving the above problem. This method uses SiC or A
l to ₂ O ₃ preform formed of ceramic powder, such as, by contacting the aluminum ingots, which N ₂
This is a method of impregnating a preform with an aluminum alloy that has been heated to 700 to 900 ° C. and melted in an atmosphere. This is an excellent method in which the preform can be impregnated with the metal without applying pressure by improving the wettability of the molten metal to the ceramic powder using a chemical reaction.

Further, according to this method, the content of ceramics can be varied as wide as 30 to 85 vol% and a high range, and the preform formed by this method has a high degree of freedom in its shape. It is also possible to make quite complex shapes with near nets. As described above, this method does not require a pressurizing device, can increase the content of ceramics, and enables near-net molding. Therefore, this method is an excellent method that solves the above-described problem. .

[0006]

However, in this manufacturing method, when a small and complicated component, for example, a bolt, is manufactured, a metal is laid on the lower side, and the head of the bolt is placed on the metal. In order to place the preform on the stand and allow the metal to penetrate the preform, the amount of metal used for penetration needs to be much larger than the amount required for penetration of the preform, and only the head of the bolt is in contact with the metal. In other words, since the contact area with the molten metal is small, the head of the preform bolt sinks into the remaining molten metal and is buried, making it difficult to separate and remove the bolt that has passed through. was there.

[0007] The present invention has been made in view of the problems of the above-described method for producing a metal-ceramic composite material, and has as its object to provide a metal-ceramic composite material which can be easily separated from the remaining metal used for infiltration. An object of the present invention is to provide a method for manufacturing a ceramic composite material.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, if a dummy preform is inserted between a molten metal and a preform, it can be easily separated from the remaining metal. The present inventors have found that the present invention can be performed, and have completed the present invention.

That is, the present invention relates to a method for producing a metal-ceramic composite material in which a preform is formed by using ceramic fibers or particles as a reinforcing material, and a metal as a base material is penetrated into the preform. However, after inserting a dummy preform in advance between the metal and the preform, an alloy containing aluminum as a main component is heated to 700 to 1000 ° C. through the dummy preform.
A method for producing a metal-ceramic composite material, characterized in that it is a method of infiltrating a preform at a temperature of This will be described in more detail below.

As described above, as a method of manufacturing a composite material, a method of infiltrating a metal is performed by inserting a dummy preform in advance between a metal and a preform, and then mainly using aluminum through the dummy preform. The manufacturing method was such that the alloy as a component was infiltrated into the preform at a temperature of 700 to 1000 ° C. By inserting the dummy preform between the metal and the preform, even if the dummy preform was buried in the remaining molten metal, the composite material impregnated with the metal was not buried in the molten metal, and was produced. The composite material can be easily separated from the dummy preform by means such as tapping.

The shape and size of the dummy preform are not particularly limited. However, it is generally desirable that the dummy preform has a flat shape and does not have a fear of sinking into the molten metal. The reason is that the contact area with the metal is large and the permeation distance is short, so that the permeation is completed in a short time and the dummy preform is easily separated because it does not sink into the molten metal.
For the ceramic powder constituting the dummy preform, use as coarse a powder as possible that can maintain the shape of the preform so as to secure a wide path for the molten metal in order to further facilitate metal penetration. Is desirable.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The production method of the present invention will be described in more detail. First, ceramic powders such as Al ₂ O ₃ powder, AlN powder and SiC powder are prepared. These powders may be used alone or another powder may be partially mixed.

Using the prepared powder, a preform intended for a bolt or the like that is likely to sink into the molten metal and a dummy preform on which the preform is mounted are formed, fired, and formed. However, a powder as coarse as possible is used for the dummy preform. The molding method may be any method as long as the shape is maintained until the permeation of the metal is completed and does not inhibit the permeation, such as a sedimentation molding method, an injection molding method, and a CIP molding method.
The injection molding method is suitable for preforms having small and complicated shapes such as bolts and gears, and the simplest and frequently used sedimentation molding method is suitable for dummy preforms.

Next, first, an alloy mainly composed of aluminum is laid, a dummy preform formed thereon is mounted thereon, and the preform is further mounted thereon in an appropriate state.
The alloy is infiltrated into the preform at a temperature of 700 to 1000 ° C. under non-pressurization in a nitrogen stream, and cooled to produce a metal-ceramic composite material. It is easier to penetrate the aluminum metal to be used if it contains Mg such as Al-Mg or Al-Mg-Si, but it is not limited to this, and the physical properties required for the final product Any aluminum alloy may be used as long as it does not contain an element that degrades aluminum. Finally, the produced metal-ceramic composite material is lightly tapped to separate it from the dummy preform to obtain a target composite material.

If a metal-ceramic composite material is produced by the above method, a metal-ceramic composite material that can be easily separated from the remaining metal can be obtained.

[0016]

EXAMPLES Hereinafter, the present invention will be described in more detail by giving specific examples of the present invention.

(Example) (1) Formation of preform Commercially available Si of # 500 (average particle size 25 μm) as a reinforcing material
To 100 parts by weight of the C powder, 7 parts by weight of a colloidal silica liquid (silica concentration: 30%) dispersed in isopropyl alcohol was added as a binder, and a binder for injection molding comprising an acrylic resin, a wax, a plasticizer, and the like was added thereto. An appropriate amount was added and kneaded to prepare a compound.
A preform having a gear shape of φ15 × 10 mm in thickness and a preform having a bolt shape of φ12 × 40 mm in length were formed from this by an injection molding machine. The obtained molded body was heated to 450 ° C. at 10 ° C./hr, held for 5 hours to remove the binder, and then cooled to room temperature at 50 ° C./hr. Then, the temperature was raised to 1200 ° C. at 100 ° C./hr,
After holding for 3 hours, the mixture was cooled at 100 ° C./hr to form a preform.

(2) Formation of dummy preform Commercially available # 180 (average particle size: 66 μm) Si as a reinforcing material
For 70 parts by weight of C powder and 30 parts by weight of commercially available SiC powder of # 800 (average particle size: 14 μm), 10 parts by weight of a colloid liquid of alumina hydrate as a binder (alumina content is 2 parts)
Then, 0.2 parts by weight of FORMASTER VL (manufactured by Sannobuco) and 24 parts by weight of ion-exchanged water were added as defoaming agents, and mixed in a pot mill containing no medium for 64 hours. The obtained slurry is poured into a 100 mm square, 10 mm thick silicone rubber mold, and a solid is settled by applying vibration to remove water floating on the surface,
It was cooled to −30 ° C. in a rubber mold to obtain a frozen product.
The obtained frozen product was removed from the mold and fired at 1050 ° C. for 3 hours to form a dummy preform.

(3) Preparation of Metal-Ceramic Composite Material Plate-shaped Al-15Si-5M 3 times the weight of the preform
spread aluminum alloy of g composition, put the obtained dummy preform on it, put it on the gear-shaped preform obtained on it, and place it sideways, and on the bolt-shaped preform with the head down It was placed upright and non-pressurized at 825 ° C. for 12 hours in a nitrogen atmosphere, and then cooled at 100 ° C./hr to produce a metal-ceramic composite material attached to the dummy preform.

(4) Evaluation The bulk density of the formed preform and dummy preform was measured by the Archimedes method, and the powder filling rate was determined. As a result, the powder filling rate of the preform was 52 vol%,
The powder filling rate of the dummy preform was 70 vol%. Further, it was examined whether the composite material stuck to the dummy preform was separated by lightly tapping. As a result, it was confirmed that the bolts as well as the gears could be easily separated from the dummy preform by only tapping lightly.

[0021]

As described above, according to the method for producing a metal-ceramic composite material of the present invention, the produced composite material can be easily separated from the remaining metal. As a result, it is possible to reduce the defective rate due to sticking of small complex parts to the remaining metal, and mass production of parts such as bolts and gears, in which the effect of the present invention is particularly remarkable, can be expected.

[Table 1]

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mutsumi Hayashi 560 Omaki, Urawa City, Saitama Prefecture (72) Inventor Heishiro Takahashi 314-1 Matsudo Nitta, Matsudo City, Chiba Prefecture (72) Inventor Tomiwa Koyama Kita, Tokyo 1-3-805

Claims (1)

[Claims] 1. A method for producing a metal-ceramic composite material in which a preform is formed by using ceramic fibers or particles as a reinforcing material, and a metal as a base material is impregnated in the preform, wherein the method for impregnating the metal is metal. And a method in which a dummy preform is previously inserted between the preform and the preform, and then the alloy containing aluminum as a main component is permeated into the preform at a temperature of 700 to 1000 ° C. through the dummy preform. A method for producing a metal-ceramic composite material.