JPH0891968A - Ceramic structure material having copper alloy layer on surface - Google Patents

Abstract

PURPOSE: To obtain a ceramic material having an easily processable metallic layer on the surface useful as a precision machinery material which requires the characteristics of light weight, low thermal expansion and high stiffness. CONSTITUTION: This ceramic material for a precision machinery is obtained by forming a copper alloy layer of 10-500μm in thickness which can be processed by machining without using a processing liquid on the surface of the ceramic 1. The obtained ceramic material can be processed in high precision by machining and keeps the features characteristic to ceramics such as low thermal expansion, high stiffness and light weight. Especially, a material having a brass layer 3 of about 150μm in thickness on the surface of ceramics as the copper alloy layer has superior characteristics to a conventional brass bulk material as a precision machinery material. Further, the brass layer surface can be processed in high precision without using processing liquid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic member for precision machinery, which is required to be lightweight, low in thermal expansion and highly rigid.

[0002]

2. Description of the Related Art Conventionally, metal materials have been applied to precision mechanical members and the like. However, due to temperature changes and elasto-plastic deformation
Since the deterioration of the device performance becomes a problem, it has been attempted to use a ceramic material having a lower thermal expansion property, heat resistance, and higher rigidity than a metal material.

The shapes of these precision machine members are various, and the dimensions are required to be highly accurate.

Since ceramics are difficult-to-process materials, it is technically difficult to meet these requirements, and there is a problem that the processing cost becomes high.

As one measure for facilitating the processing of ceramic members, attempts have been made to form a metal layer on the surface of ceramics.

[0006] However, as the material of the metal layer, no one has been selected by paying particular attention to easy workability. For example, the formation of a pure metal film such as Cu, Ni, Fe or the like, which is focused only on the adhesion of ceramics, is preferable. Was the Lord.

Therefore, during processing, although processing is superior to ceramics, a processing liquid must be used, and it is unsuitable as a precision member which requires cleanliness to avoid rusting of metal layers and contamination of members. .

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to
(1) A ceramic structural member that can be processed with high precision dimensions, (2) does not impair the characteristics of ceramics (low thermal expansion, high rigidity, light weight, etc.), and (3) is easy to process and has little pollution associated with processing. Is to provide.

[0009]

According to the present invention, a ceramic structure member having a copper alloy layer having a thickness of 10 to 500 μm formed on a ceramic surface and excellent in high precision workability, or a metallized layer having a thickness of 5 to 20 μm on the ceramic surface. Formed to a thickness, and a copper alloy layer having a thickness of 10 to 500 μm on the metallized layer.
It is an object of the present invention to provide a ceramics structural member formed in a thickness and excellent in high-precision workability.

Brass or bronze is desirable for the copper alloy layer formed on the ceramic surface.

These alloys have excellent workability such as cutting or grinding. Therefore, if the alloy layer is finely modified, a cutting or grinding tool can be used without using a working fluid such as water or oil. Highly accurate processing is possible without seizing or clogging.

The minimum thickness range of the metal layer is 10 μm, which is the minimum thickness required for processing in the case of pursuing dimensional accuracy, and the maximum thickness of 500 μm is more than this. In that case, there is a possibility that the properties such as low thermal expansion or high rigidity of the ceramic properties expected as the ceramic structure may be impaired. The manufacturing method of the present invention will be described below.

In addition to forming the copper alloy layer directly on the surface of the ceramic, it is recommended to subject the surface of the ceramic to a metallizing treatment for a member for which the adhesion between the copper alloy layer and the ceramic is particularly required.

The appropriate thickness of the metallized layer is 5 to 20 μm. This is because if it is 5 μm or less, the effect of improving the adhesion between the copper alloy layer and the ceramic is not exhibited, and if it is 20 μm or more, the characteristics of the member (easy workability, high rigidity, low thermal expansion) are deteriorated.

Examples of the metallizing treatment include commercially available noble metal-based Ag-based powder or active metal-based A
A paste prepared by mixing g-Cu-Ti alloy powder and oil is applied to the ceramic surface. In the case of Ag paste, it is in the air, and in the case of Ag-Cu-Ti paste is in vacuum (10 ^-6
It is suitable to perform a heat treatment at 850 ° C. for each torr to form a metallized layer.

The formed metallized layer is capable of forming a copper alloy layer having a strong adhesion by adhering ceramics and a copper alloy and diffusing the components thereof into both materials.

Specific methods for forming the copper alloy layer on the surface of the ceramics or the surface of the metallized layer include a joining method and a thermal spraying method.

For example, in the joining method, a thin plate of copper alloy (thickness: 10 to 500 μm) prepared in advance is placed on the surface of the ceramic or the surface of the metallized layer and joined by heat treatment. The thermal spraying method uses a thermal spraying gun incorporating a lead wire of a copper alloy component, and a thermal spraying layer (thickness 10 to 500
μm) is formed.

The features of the ceramic structural member of the present invention are:
Since the easily processable metal layer is formed on the surface, the correction process is easy and the highly accurate dimension can be revealed.

From the above, the member of the present invention is applied to a member for precision machinery which is required to have dimensional accuracy, complicated shape, low thermal expansion property, high rigidity and light weight.

For example, with respect to dimensional accuracy, the copper alloy layer on the ceramic surface can be easily machined without using a working liquid, and a difficult-to-machine ceramic member can be provided as a member with high dimensional accuracy at low cost. Means that there are benefits.

Further, for a product having a complicated shape, if a near net shape ceramics fired body is roughly processed, a copper alloy layer is formed on the surface thereof, and the alloy layer is machined to have a complicated shape. Good.

With respect to any of the processing requirements, the surface of the copper alloy layer can be machined without using a machining liquid, so that the ceramic member can be always placed in a clean environment.

[0024]

EXAMPLE Ceramics 1 is a material called fine ceramics such as alumina, sialon, silicon nitride, silicon carbide and zirconia which are on the market today.

The shape is a □ 50 × 5 mm plate, and the surface (50
The brass film 2 was formed on the (× 50 surface).

Ag-Cu is formed on the surface of each ceramic.
— A paste obtained by mixing Ti-based alloy powder and oil was applied, and heat treatment was performed at 850 ° C. in vacuum (10 ⁻⁶ torr) to form a metallized layer. The metallized layer had a thickness of about 10 μm.

Next, a brass layer (70 wt% Cu-30 wt% Zn) was formed on the metallized surface by a bonding method or a thermal spraying method (FIG. 1).

The joining method was carried out by placing a 150 μm brass thin plate on the metallized surface and applying no load in a vacuum (10 ⁻⁶ torr).
The brass layer was formed on the ceramic surface by heat treatment at a maximum temperature of 900 ° C.

In the thermal spraying method, a brass component lead wire is installed in a thermal spray gun, and about 1 is obtained by arc thermal spraying in the atmosphere.
A brass sprayed layer of 50 μm was formed.

Particularly, for alumina ceramics,
Under the same conditions as the above-mentioned joining method and thermal spraying method, the brass layer (about 150 μm) was directly applied to the ceramic surface without metallization treatment.
m) was formed.

The density, thermal expansion coefficient and Young's modulus of the ceramic member having the brass layer formed thereon were measured and compared with those of the ceramic alone or the brass alone. The results are shown in Table 1.

Each value of the ceramic members in the table is an average value of the members by various methods adopted for forming the brass layer.

The characteristics of the ceramic member of the present invention are as follows. A member made of only metal such as brass (density = 8.55 g /
cm ³ , thermal expansion coefficient = 16.0 × 10 ⁻⁶ / ° C., Young's modulus = 1.03 × 10 ⁴ kg / mm ² ), which proved to be suitable for precision machine parts.

Further, surface grinding is performed at 50 μm on all the ceramic members on which the brass layer is formed without using a working liquid.
When the metal layer was applied, a clean surface was obtained without peeling or cracking of the brass layer regardless of the presence or absence of the metallized layer.

[0035]

[Table 1]

[0036]

EFFECTS OF THE INVENTION The copper alloy layer formed on the surface of the ceramics, which has excellent machinability, enables machining without a machining fluid, so that the ceramics member can always be placed in a clean environment, and rust and contamination can be prevented. It was possible to apply to precision mechanical parts that require ceramic characteristics without worry.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a ceramic member having a brass layer formed thereon.

[Explanation of symbols]

 1 Ceramics 2 Metallized layer 3 Brass

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hidehiko Morita 2-6-3 Otemachi, Chiyoda-ku, Tokyo Shin Nippon Steel Corporation

Claims (2)

[Claims] 1. A copper alloy layer having a thickness of 10 to 5 on the ceramic surface.
A ceramic structure member with a high precision workability formed with a thickness of 00 μm. 2. A metallized layer of 5 to 5 is formed on the surface of ceramics.
A ceramic structural member excellent in high-precision workability, which is formed to a thickness of 20 μm, and a copper alloy layer is formed to a thickness of 10 to 500 μm on the metallized layer.