JP2809384B2 - Aluminum alloy composite manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a composite material in which a matrix metal of an aluminum alloy is naturally penetrated into a preform of, for example, alumina short fibers to form a composite.

[0002]

2. Description of the Related Art Conventionally, when an aluminum alloy is naturally penetrated (no pressure applied) into a preform of alumina short fiber to form a composite, it is necessary to improve the wettability between the alumina fiber and the molten aluminum alloy. For this reason, for example, Mg
Mg ₃ N _{2 on} the surface of alumina fiber by gas and N ₂ gas
The surface of the fiber is reduced and activated by Mg ₃ N ₂ to improve the wettability, and the molten aluminum alloy is introduced into the preform by the capillary phenomenon through the gap between the fibers to form a composite. The technology is known. At this time, it is known that complexing is possible if an aluminum alloy containing magnesium is used as a matrix metal as a supply source of Mg gas. When an aluminum alloy is used as a matrix metal, for example, a technique disclosed in Japanese Patent Publication No. Hei 5-507030 is known.

In this technique, as shown in FIG. 2, a graphite ring 52 is superposed on a preform 51 containing magnesium, and a colloidal graphite 53 is applied around the preform 51 by aerosol spray coating and dried. Placed in a granular alumina 55 filled in a graphite container 54, a space 56 in a graphite ring 52 is filled with magnesium powder, and a matrix metal ingot 57 made of pure aluminum metal is placed on the graphite ring 52. An apparatus of this kind is disclosed.

[0004]

In the above-mentioned apparatus, the preform containing magnesium is improved by improving the wettability of the preform itself by the reducing action of the magnesium contained therein so that the molten matrix alloy is infiltrated into the preform. It is something to be manufactured. The device is significant in that it allows natural penetration. However, in the device, the preform and the matrix alloy are only separated by a space via a graphite ring. Therefore, when the temperature is raised, mp (melting temperature)
At first, the matrix alloy melts and comes into contact with the preform, but at this time, the magnesium contained in the preform has not reached the subliming temperature or has not sufficiently sublimated. Therefore, the inside of the preform is not sufficiently wetted, the molten matrix alloy does not sufficiently penetrate into the preform, and a high-quality composite material cannot be obtained.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an apparatus for manufacturing an aluminum alloy composite material in which an aluminum alloy is naturally infiltrated into a preform made of a metal oxide to form a composite. And a second mold mounted on the top of the aluminum alloy ingot and having a communication hole at the bottom in the first mold, and a communication hole on the bottom surface of the second mold is provided. Sealing is performed with a sealing member that melts at a predetermined temperature, and a penetration enhancing material is accommodated in the second mold, and abuts or fits on the inner wall surface of the second mold above the penetration enhancing material. Preforms to be combined were placed. The sealing member was made of a metal having a higher melting point than the aluminum alloy ingot, and was made of, for example, pure aluminum. The penetration enhancer was magnesium.

[0006]

When the temperature of the furnace is increased to a temperature lower than the melting point of the sealing material and higher than the melting point of the penetration enhancer (above the melting point of the aluminum alloy ingot) after the apparatus is decompressed in, for example, a vacuum furnace. Sublimates and penetrates into the inside of the preform. At this time, if the penetration enhancer is magnesium, the surface is reduced and activated by introducing N ₂ gas into the vacuum furnace to generate Mg ₃ N ₂ on the fiber surface of the preform. At the same time, the aluminum alloy ingot also melts, but cannot enter the second mold by the sealing member, during which time the wettability of the fiber surface of the preform is sufficiently improved.

When the temperature in the furnace is further increased to a temperature equal to or higher than the melting point of the sealing member, the sealing member is melted to communicate with the communication hole on the bottom surface of the second mold, and the molten aluminum alloy enters the second mold. I do. Then, the molten metal comes into contact with the preformed body, and penetrates between the fibers having improved wettability by capillary action to form a composite.
Here, if pure aluminum is used as the sealing member, the melting point can be made higher than that of the aluminum alloy ingot, and when melted, it is of the same quality as the aluminum alloy ingot, which is convenient.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A manufacturing apparatus according to the present invention will be described with reference to the schematic diagram of FIG. The apparatus for manufacturing an aluminum alloy composite material of the present invention uses an aluminum alloy as a matrix metal serving as a metal base material, and forms a composite material by natural infiltration without pressure. As shown in FIG. 1, for example, a first mold 1 made of ceramics and a second mold 2 made of graphite, ceramics, etc.
It has.

An aluminum alloy ingot 3 is accommodated inside the first mold 1 as a matrix metal, and the second mold 2 is set on the upper part of the aluminum alloy ingot 3. Further, the second mold 2 has a communication hole 2a on the bottom surface, and a sealing member 4 such as pure aluminum having a melting point higher than that of the aluminum alloy ingot 3 is fitted into the communication hole 2a in close contact with the communication hole. 2a is sealed.

A predetermined amount of a permeation enhancer 5 such as magnesium is accommodated in the second mold 2, and a preform made of short alumina fibers or the like is provided above the permeation enhancer 5. Are arranged. The preform 6 is in contact with or fitted to the inner wall surface of the second mold 2 and is in close contact with the inner wall of the second mold 2 without any gap.

The above-described apparatus is set in a vacuum furnace, and the pressure is reduced to, for example, about 10 mmHg or less.
The heating is performed at a temperature above the melting point of the sealing member 4 such as pure aluminum. As a result, the penetration enhancer 5 such as magnesium sublimates and effectively penetrates into the preform 6 because there is no other escape place. Here, when the permeation enhancer 5 is magnesium and Mg gas sublimes, N ₂ gas is introduced into the furnace up to 1 atm to generate Mg ₃ N ₂ to coat the fiber surface and improve wettability. . At this time, the aluminum alloy ingot 3 in the first mold 1 is also melted, but does not contact the preform 6 because the sealing member 4 seals the communication hole 2a. Is sufficiently improved.

Thereafter, if the temperature in the furnace is raised to the melting point of the sealing member 4 or higher, and the sealing member 4 is melted to communicate with the communication hole 2a, the wettability of the fibers of the preform 6 is sufficient at this point. Because of the improvement, the compounding by natural permeation is smoothly performed by the capillary phenomenon.

Next, a specific embodiment of the present invention will be described. The first mold 1 has an inner diameter of 100 mm and a height of 200 mm.
mm alumina tray is prepared and JIS
AC4C aluminum alloy ingot 3 (φ98mm,
(Height 60 mm).

Next, the aluminum alloy ingot 3
A second mold 2 made of a graphite crucible having an inner diameter of 60 mm and a height of 100 mm is set on top of this, and a communication hole 2 a having a diameter of about 15 mm on the bottom surface of the second mold 2 is sealed with a pure aluminum sealing member 4.
Stoppered. Then, the permeation enhancer 5 is placed in the second mold 2.
7g of pure magnesium, and a diameter of 60g
An alumina short fiber preform 6 mm and 60 mm in height was tightly fitted. Incidentally, the fiber content (Vf) of the preform 6 is 30%.

The first mold 1 set as described above is placed in a vacuum furnace, and the pressure is first reduced to 0.1 mmHg in the manner shown in FIG. 3 and then heated to 640 ° C. at a rate of 10 ° C./min.
Hold for 5 minutes. Thereafter, N ₂ gas was introduced into the vacuum furnace to 1 atm. Then, at a heating rate of 10 ° C./min, 72
When heated to 0 ° C., held for 20 minutes and cooled in the furnace, the preform 6 was completely composited. In the present invention, it goes without saying that the aluminum alloy ingot 3 has no problem even if the magnesium content is large.

Incidentally, the sealing member 4 as described above exhibits a so-called time-consuming function until the preform 6 is reduced and the wettability is improved. Usually, such a composite material type is for a single item, and is usually broken when used once. Therefore, an inexpensive configuration such as the present invention is particularly useful. is there.

[0017]

As described above, the apparatus for manufacturing an aluminum alloy composite according to the present invention seals the communication hole formed in the bottom surface of the second mold with the sealing member and penetrates until the sealing member is melted. The accelerating material is sufficiently penetrated into the preform to improve the wettability, and at the same time, the aluminum alloy ingot is melted, and then the sealing member is melted and the molten aluminum alloy is formed into the preform through the communication hole. Since the contact is made, natural infiltration is performed smoothly, and a high-quality aluminum alloy composite material can be obtained. Further, the apparatus is simple and inexpensive, and the work is simple and no work time is required.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of the configuration of the present manufacturing apparatus.

FIG. 2 is a conventional configuration diagram.

FIG. 3 is an embodiment diagram showing an example of a processing procedure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 1st casting mold, 2 ... 2nd casting mold, 3 ... Aluminum alloy ingot, 4 ... Sealing member, 5 ... Penetration promoting material, 6 ... Preform.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B22D 19/14 B22D 21/04

Claims (4)

(57) [Claims] 1. An apparatus for manufacturing an aluminum alloy composite material in which an aluminum alloy is naturally infiltrated into a preform made of a metal oxide to form a composite, the apparatus comprises a first mold for housing an aluminum alloy ingot, and a A second mold which is placed in the upper part of the aluminum alloy ingot in the first mold and has a communication hole in a bottom part, and a sealing member which melts the communication hole in the bottom surface of the second mold at a predetermined temperature. In addition to sealing, the penetration promoting material is accommodated in the second mold, and the preform which is in contact with or fits on the inner wall surface of the second mold is disposed above the penetration promoting material. An apparatus for producing an aluminum alloy composite material. 2. The apparatus according to claim 1, wherein the sealing member is made of a metal having a higher melting point than the aluminum alloy ingot. 3. The apparatus according to claim 2, wherein said sealing member is made of pure aluminum. 4. The apparatus for manufacturing an aluminum alloy composite according to claim 1, wherein the penetration enhancer is made of magnesium.