JPH11170027A - Ingot for metal-ceramic composite and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ingot for metal-ceramic composite without containing elements easily volatilized, and a producing method thereof. SOLUTION: In the ingot for metal-ceramic composite, in which the metal as the base material is impregnated into the ceramic grain as the reinforcing material, the ceramic grain is composed of SiC grain having 25-40 vol.% grain content and 15-60 μm average grain diameter, and the metal is composed of aluminum containing 5-15 wt.% Si or the alloy thereof. In the producing method, the SiC grain having 15-60 μm average grain diameter is filled into a mold of metallic mold, etc., so that the grain content ratio becomes 25-40 vol.%, and the aluminum containing 5-15 wt.% Si or the alloy thereof is impregnated into the SiC grain with a high pressure casting method and then, they are mechanically stirred.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal-ceramic composite material using aluminum or its alloy as a metal, and more particularly to an ingot used as a raw material of the composite material and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a metal-ceramic composite material having aluminum or its alloy as a base material is heated and melted at a temperature higher than a melting point, and particles such as silicon carbide are added to the molten metal. And then injected into a mold such as a mold or sand mold. According to this method, a product having a large degree of freedom in the shape of a product and a relatively large shape can be manufactured. However, according to this method, the content of the ceramic particles can be increased only to at most 20% by volume, and a composite material having sufficient strength and rigidity cannot be obtained.

[0003] Therefore, in order to increase the content of ceramic particles, a so-called high-pressure casting method has been proposed in which a preform is formed from ceramic particles or fibers such as silicon carbide, and the preform is pressurized and impregnated with a molten metal. . According to this method, since the content of the ceramic particles can be set to 30% by volume or more, a composite material having high strength and high rigidity characteristics can be produced. However, in this method, a pressure-resistant mold is required to impregnate the molten metal into the preform at a high pressure, and the pressure-resistant mold has a shape restriction, so that a complicated-shaped product or a large-sized product is manufactured. There were problems such as difficulty.

In order to solve these problems, the wettability of aluminum and ceramic particles in aluminum or an alloy thereof is improved, and Li, Ca, Mg, etc., which allow the molten metal to penetrate the ceramic particles without pressure. A method has been proposed in which an ingot is prepared by adding an element, melting the element and infiltrating the ceramic particles, and recasting the ingot to produce a composite material having a desired shape. In this method, the content of the ceramic particles can be increased to 30% by volume or more as described above, so that high strength,
A composite material having high rigidity characteristics can be manufactured,
In addition, the re-casting makes it possible to produce a complicated-shaped product or a large-sized product, and eliminates the need for a large and expensive pressing device.

[0005]

However, in the ingot obtained by this method, since the added element is liable to volatilize at a low temperature, the composite material produced from the ingot is used in a heated atmosphere. There is a problem that the added element is volatilized and becomes a contaminant. In particular, it is difficult to apply to a material used in a vacuum apparatus such as CVD or PVD for manufacturing a semiconductor or a liquid crystal.

The present invention has been made in view of the above-mentioned problems of the ingot for a metal-ceramic composite material, and has as its object to provide an ingot for a metal-ceramic composite material containing no volatile element. Another object of the present invention is to provide a manufacturing method thereof.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and have found that SiC is used as a reinforcing material.
Using particles, filling the particles into a mold, and filling the filled Si
The present invention was completed based on the finding that if C particles were impregnated with aluminum containing Si or its alloy by a high-pressure casting method, an ingot for a metal-ceramic composite material containing no volatile element could be obtained.

That is, the present invention relates to (1) a metal-ceramic composite ingot in which ceramic particles as a reinforcing material are impregnated with a metal as a substrate, wherein the ceramic particles have a particle content of 25 to 40% by volume. And 1
Consisting of SiC particles having an average particle size of 5 to 60 μm,
A metal-ceramic composite ingot (claim 1), wherein the metal is aluminum or an alloy thereof containing 5 to 15% by weight of Si;
(2) In a method for producing an ingot for a metal-ceramic composite material, in which ceramic particles as a reinforcing material are impregnated with a metal as a base material, the method for impregnating the metal is such that the average particle size of 15 to 60 μm is set in a mold such as a mold. SiC particles having a diameter are filled so that the particle content is 25 to 40% by volume, and the filled SiC particles are impregnated with aluminum or an alloy thereof containing 5 to 15% by weight of Si by a high-pressure casting method. It is a gist of the present invention to provide a method for producing an ingot for a metal-ceramic composite material (claim 2), wherein the ingot is mechanically stirred. This will be described in more detail below.

The ceramic particles in the ingot have a particle content of 25 to 40% by volume, and
It is assumed that the ceramic particles are made of SiC particles having an average particle size of ６０60 μm,
An ingot for a metal-ceramic composite material comprising aluminum or an alloy thereof containing 5 to 15% by weight of Si is provided (claim 1). The reason why the ceramic particles are SiC particles is that uniform dispersion can be achieved because the difference in specific gravity from aluminum is small.

The particle content of the SiC particles is 25-40.
If the volume ratio is lower than 25% by volume, it is difficult to obtain a composite material having sufficient rigidity.
If the ratio exceeds, the flowability of the molten metal during recasting is extremely deteriorated, so that it is difficult to obtain a target shape. Further, the fineness of the SiC particles is adjusted to an average particle size of 15 to 60 μm.
If m is smaller than 15 μm, particles are difficult to disperse, mechanical stirring during casting is difficult, and particles are easily aggregated even when dispersed, flowability deteriorates, and stable physical properties are obtained. This is because it is difficult to produce a composite material having the same. Conversely, if it is coarser than 60 μm, the particles settle due to stirring during casting, and the concentration distribution of SiC particles in the produced composite material becomes non-uniform.

On the other hand, the reason why the impregnated metal is aluminum containing Si or an alloy thereof is that if not containing Si, molten Al and SiC react with each other to form Al ₄ C ₃ and deteriorate the material properties. Si in the metal to suppress the reaction
Is to be included. The content is preferably 5 to 15% by weight, and if it is less than 5% by weight, the effect of suppressing the generation of Al ₄ C ₃ is small, and the fluidity of the molten metal during casting is reduced. Metal does not spread in the mold. Conversely, if the content is more than 15% by weight, aluminum or its alloy as a matrix becomes brittle and loses ductility.

As a manufacturing method for manufacturing the ingot, first, a mold such as a mold is filled with SiC particles having an average particle diameter of 15 to 60 μm so that the particle content is 25 to 40% by volume, and the filling is performed. 5-15 Si on the SiC particles
After impregnating aluminum or its alloy containing by weight by a high-pressure casting method, it is a manufacturing method of mechanically stirring it (claim 2). According to this manufacturing method, by injecting a molten metal at a high pressure, the metal can be impregnated without adding an element such as Mg as in the case of the preform. Therefore, mechanical agitation is possible because of such restraint, and the ingot can be manufactured by performing the mechanical agitation. As a result, an ingot for a metal-ceramic composite material containing no volatile element can be obtained. By re-casting the ingot, it is possible to produce a complex-shaped product or a large-sized product.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The production method of the present invention will be described in more detail. First, SiC particles (powder) having an average particle size of 15 to 60 μm are prepared as a reinforcing material. As the SiC particles, commercially available products may be used, or the SiC particles may be manufactured in-house by a commonly used method.

After heating the particles at 800 ° C., they are filled into a mold such as a mold so as to have a content of 25 to 40% by volume.
Separately, aluminum or an alloy thereof containing 5 to 15% by weight of Si heated and melted at a predetermined temperature is poured into a mold, and a metal is impregnated between SiC particles at a predetermined pressure by a conventional high-pressure casting method, and this is mechanically stirred. After cooling, an ingot for a metal-ceramic composite material is produced. The ingot is melted again, mechanically stirred, poured into a mold such as a sand mold or a mold, cooled, and taken out to obtain a composite material having a desired shape.

When an ingot is manufactured by the above-described method, an ingot for a metal-ceramic composite material containing no volatile element can be obtained.

[0016]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples of the present invention and Comparative Examples.

(Examples 1 to 7) (1) Preparation of ingot for metal-ceramic composite material In a high-pressure casting mold (inner diameter 55 mm) preheated to 300 ° C, average grains shown in Table 1 were preheated to 800 ° C. S with diameter
The iC particles were filled so as to have a content shown in Table 1, and 170 g of a molten aluminum alloy containing Si in an amount shown in Table 1 which was heated and melted at 800 ° C. was poured therein, and the pressure was 600 kg / kg.
After pressurizing at ² cm ² , the SiC particles were impregnated with an aluminum alloy, cooled, and taken out of the mold. Then add 45g of the same aluminum alloy and place in a carbon crucible for 8
After re-melting at 00 ° C. and performing mechanical stirring, it was cooled to produce an ingot. The particle content is determined by the amount of S
Since it can be obtained by the ratio of the amount of the iC powder and the amount of the aluminum alloy to be injected, the amount of the aluminum alloy was made constant (170 + 45 g) and adjusted by changing the amount of SiC.

(2) Evaluation The obtained ingot was re-melted and opened in a firebrick.
A sample that was poured into a hole of 12 × h30 mm and completely filled was evaluated as having good fluidity (）), and a sample that was not completely filled was evaluated as poor fluidity (×). After further mechanical stirring, the mixture was poured into a mold of φ50 × h40 mm, a 40 × 4 × 3 mm test piece was cut out from the obtained composite material, and the Young's modulus and elongation of the test piece were measured by a tensile test (JIS Z). 22
41). Furthermore, the cut surface obtained by cutting the test piece was observed with an optical microscope to check the dispersion state of the SiC particles.
A sample having good dispersibility was evaluated as ○ and a sample having poor dispersibility was evaluated as ×.
Table 1 shows the results.

(Comparative Examples 1 to 6) For comparison, in Comparative Examples 1 and 2, the particle content of the SiC particles was out of the range of the present invention, and in Comparative Examples 3 and 4, the average particle size was determined according to the present invention. In addition, in Comparative Examples 5 and 6, ingots were produced and evaluated in the same manner as in Example 1 except that the content of Si in the alloy was out of the range of the present invention. Table 1 shows the results.

[0020]

[Table 1]

As is clear from Table 1, in each of the examples, the fluidity of the molten ingot was good, and
The Young's modulus and elongation of the obtained composite material and the dispersion state of the SiC powder were also good. In contrast, in Comparative Example 1,
Since the particle content of the SiC particles was low, the Young's modulus of the composite material was low. In Comparative Example 2, since the particle content was high,
The fluidity was poor, and the desired shaped article could not be cast. In Comparative Example 3, since the SiC particles were too fine, the fluidity was poor, the particles aggregated and the dispersed state was poor, and the Young's modulus and elongation of the composite material were not measured. In Comparative Example 4, although the fluidity was good, the SiC particles were too coarse, the particles settled and could not be uniformly dispersed, and the Young's modulus and elongation of the composite material were not measured. Furthermore, in Comparative Example 5, since the amount of Si in the alloy was small, the fluidity was poor, a desired shaped product was not obtained, and the Young's modulus and elongation were not measured. In Comparative Example 6, since the amount of Si was large, the elongation percentage of the composite material was extremely small, and the composite material lost ductility.

[0022]

As described above, according to the present invention, an ingot for a metal-ceramic composite material containing no volatile element can be obtained. Thus, the metal-ceramic composite material produced from the ingot obtained by the present invention can be applied to a material used in a vacuum apparatus such as CVD or PVD for producing semiconductors and liquid crystals.

Claims (2)

[Claims] 1. An ingot for a metal-ceramic composite material in which ceramic particles as a reinforcing material are impregnated with a metal as a base material, wherein the ceramic particles are 25 to 40.
It consists of SiC particles having a particle content of volume% and an average particle size of 15 to 60 μm, wherein the metal comprises 5% Si.
An ingot for a metal-ceramic composite material comprising aluminum or an alloy thereof containing up to 15% by weight. 2. A method for producing an ingot for a metal-ceramic composite material in which ceramic particles as a reinforcing material are impregnated with a metal as a base material, wherein the method for impregnating the metal is 15 to 60 μm in a mold such as a mold. SiC with average particle size
The particles are filled so as to have a particle content of 25 to 40% by volume, and the filled SiC particles are impregnated with aluminum or an alloy thereof containing 5 to 15% by weight of Si by a high-pressure casting method, and then mechanically stirred. A method for producing an ingot for a metal-ceramic composite material, comprising: