JPH11340640A - Electronic apparatus cabinet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize miniaturization and weight reduction and improve radiation performance by constituting SiC in a specified range of vol.% in a cabinet, and constituting the residue of composite material whose main component is aluminum or an aluminum alloy. SOLUTION: SiC powder of 15-40 vol.% is added to aluminum alloy molten metal of specified composition. By stirring, mixing and casting, ingot composed of aluminum or aluminum alloy/SiC based composite material is formed. By rolling the ingot, five kinds of plate materials of 0.4 mm in thickness are obtained. By press-working the plate materials, a cabinet of a note book type personal computer which has an external dimension of 280 μm in length and 210 mm in width is formed, thereby improving strength without hardly deteriorating the thermal conductivity and mold workability, and therefore reducing the thickness of a cabinet. As a result, thermal resistance is lowered, and an electronic equipment cabinet which is small-sized, lightweight and satisfactory in radiation performance can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a housing used for electronic equipment such as a small personal computer and a measuring instrument.

[0002]

2. Description of the Related Art Conventionally, plastics, magnesium alloys, aluminum alloys, and the like have been used as materials for housings used in electronic devices such as small personal computers, particularly portable notebook personal computers and measuring instruments.

However, in recent years, as the degree of integration of semiconductor elements has increased, the amount of heat generated by the semiconductor elements has increased. On the other hand, due to the miniaturization of equipment, the structure tends to be difficult to dissipate heat.
In particular, small portable devices are hermetically or semi-hermetically sealed by a housing, so that the heat radiation characteristics from the housing are regarded as important.

[0004]

However, plastic housings have insufficient heat dissipation due to poor thermal conductivity of plastics, and magnesium alloys and aluminum alloys have been developed to solve this problem. In order to secure a sufficient strength, it is necessary to make the housing relatively thick, 0.8 to 1.0 mm, in order to secure sufficient strength. turn into. The present invention has been made in view of the above circumstances, and has as its object to provide a housing for an electronic device that is small and lightweight and has excellent heat radiation characteristics.

[0005]

In order to solve the above-mentioned problems, the present invention is characterized in that SiC is comprised of a composite material containing 15 to 40% by volume of SiC and the balance being aluminum or an aluminum alloy as a main component. To provide an electronic device housing.

[0006] In the electronic device housing of the present invention thus configured, the content of SiC in the composite material is 15 to 40.
%, More preferably 17 to 25% by volume. When the content of SiC in the composite material is less than 15% by volume, it is not possible to obtain an electronic device housing having sufficient strength. On the other hand, when the content exceeds 40% by volume, it is difficult to form and process the composite material. Because it becomes.

[0007] SiC can be used in the form of powder, short fibers, whiskers, etc., but is preferably used in the form of powder. The reason is that the isotropic property is easily obtained and the workability such as rolling is good, and that it can be manufactured at low cost (1/10 or less) as compared with the case of short fibers or whiskers. .

In the case of powder, it is preferable that the particles have an average particle diameter of 0.5 to 30 μm. Particularly, the average particle size is 9 to 18 μm.
More preferably, the particles are m. If the average particle size of SiC is less than 0.5 μm, sufficient dispersion cannot be performed during dissolution,
Variations in characteristics are likely to occur, and if it exceeds 30 μm,
Plastic working becomes difficult, and the particles tend to break.

The composite metal plate is preferably a rolled plate having a thickness of 0.2 to 3 mm. If the thickness of the rolled sheet is less than 0.2 mm, it is difficult to obtain sufficient strength because it is too thin.
If it exceeds mm, not only the weight of the electronic device housing cannot be reduced, but also it becomes difficult to obtain sufficient heat radiation characteristics.

[0010] The composite metal plate can be obtained by various known methods. For example, it can be obtained by stirring and mixing SiC in a molten metal of Al or Al alloy, dispersing and casting, forming an ingot, and extruding or rolling it.

Alternatively, a preform of SiC particles is formed, and Al or Al is inserted between the SiC particles of the preform.
Molten metal infiltration method of impregnating molten alloy, forming SiC particles and Al or Al alloy particles by adding a binder,
Powder metallurgy method of sintering, Al or A to SiC particles
It can also be formed by a hot press method or the like of pressing and heating a material coated with an alloy.

According to the electronic device housing configured as described above, since the electronic device housing is made of a composite material containing aluminum or an aluminum alloy as a main component and containing 15 to 40% by volume of SiC, the aluminum or aluminum alloy is excellent. The strength can be improved without substantially impairing the heat conductivity and the moldability. As a result, even if the thickness of the housing is reduced, no elastic deformation occurs, and by reducing the thickness of the housing, the thermal resistance is reduced and the heat radiation characteristics can be improved. As a result, it is possible to obtain a small and lightweight electronic device housing having good heat radiation characteristics.

[0013]

Embodiments of the present invention will be described below. A notebook PC housing was created as follows. First, Al having a composition as shown in Table 1 below was used.
The SiC powder is added to the molten alloy, stirred, mixed, and cast to form an ingot made of an Al / SiC-based composite material, and the ingot is rolled to obtain five types of 0.4 mm thick.
Was obtained. This plate material was pressed to form a notebook computer case (sample Nos. 1 to 5) having external dimensions of 280 mm in length and 210 mm in width. At this time, the thickness of the entire personal computer could be set to 30 mm.

For comparison, an Al alloy having the composition shown in Table 1 below was rolled to obtain a plate having the same thickness of 0.4 mm as described above. This plate material is pressed and the outer dimensions are 280m long
m, 210 mm wide notebook PC housing (sample N
o. 6) was prepared. At this time, since the strength of the housing was insufficient, it was necessary to insert reinforcing ribs having a thickness of 2 mm in some places, so that the thickness of the entire personal computer was 34 mm.

Electronic devices were mounted on these six types of housings, and the temperature (maximum ultimate temperature) at the center of the personal computer when operated for 1 hour in a room at a temperature of 20 ° C. was measured. The results are shown in Table 1 below.

[0016]

[Table 1]

From Table 1 above, it can be seen that Sample N within the scope of the present invention
o. When the case of 1 to 5 is used, the maximum attained temperature is
It did not exceed the standard value of 40 ° C., and all satisfied the requirements of the standard. On the other hand, the sample Nos.
When the case of No. 6 was used, the maximum attained temperature exceeded the standard value of 40 ° C. This is probably because the space formed by the reinforcing ribs impaired the heat radiation effect.

The sample No. 1 according to the comparative example was used. In order to use the Al alloy having the composition of No. 6 and not use the reinforcing rib,
The thickness of the plate material must be further increased. In such a case, not only does the weight increase, but also the heat dissipation effect is impaired.

[0019]

As described above, according to the present invention,
Since it is composed of a composite material containing aluminum or an aluminum alloy containing 15 to 40% by volume of SiC as a main component, excellent heat conductivity and moldability of aluminum or an aluminum alloy are hardly impaired.
The strength can be improved, and as a result, it is possible to obtain an electronic device housing which is small and lightweight and has good heat radiation characteristics.

Claims (3)

[Claims] 1. An electronic device housing comprising a composite metal plate containing 15 to 40% by volume of SiC and the balance being a composite material containing aluminum or an aluminum alloy as a main component. 2. The electronic device casing according to claim 1, wherein the SiC is a particle having an average particle size of 0.5 to 30 μm. 3. The electronic device housing according to claim 1, wherein said composite metal plate is a rolled plate having a thickness of 0.2 to 3 mm.