JP2522124B2 - Method of joining ceramics to ceramics - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining ceramics together.

[0002]

2. Description of the Related Art Conventionally, in order to bond a powder compact such as ceramics to a metal, first, the surface of the ceramic is Mo.
It is metallized by the -Mn method (telefken method), then nickel (Ni) plating is applied, and if necessary, an intermediate material for buffering stress is used, and the metal is brazed with silver (Ag) solder or the like. Japanese Unexamined Patent Publication (Kokai) No. 60-145972 proposes a bonded body of ceramics and a metal, which uses a copper or molybdenum plate having a thermal expansion coefficient similar to that of the ceramics as a cushioning material.

The applicant of the present invention has previously filed a patent application (Japanese Patent Application No. 1-313223) for an invention in which a nickel plate plated with chrome is used for joining at the same time as metallization. This is a method in which a nickel plate preliminarily plated with chrome and a cushioning material are interposed between ceramics and stainless steel, and heated and pressed in a vacuum atmosphere with a vacuum degree of about 10 ⁻³ to 10 ⁻⁵ Torr to join them. .

[0004]

In the conventional method of joining ceramics and metal, metallization of the ceramics surface and plating process are required before brazing the ceramics and the metal, so that the working efficiency is poor, and the silver soldering is not performed. In the case of using, since the melting point of silver is low, the heat resistance of the bonded body becomes low.
In the invention of the above-mentioned prior application, metallization and bonding can be performed at the same time, but a step of performing chromium plating in advance is required, and it is difficult to optimally control the film thickness of this chromium. Also, no consideration is given to the joining of ceramics. It is an object of the present invention to provide a method of joining ceramics that can join the ceramics with each other with high efficiency and with high joining strength.

[0005]

Means for Solving the Problems The present invention, between the Semikkusu and ceramics, Knitting forming the chrome thin film layer
This is a method of joining ceramics in which a bonding plate made of a Kell plate is arranged such that the chrome thin film layer faces both ceramics, and the ceramics are heated and pressed in a predetermined vacuum state.

[0006]

The chrome layer of the joining plate comes into contact with the ceramic to metallize its surface, and at the same time, the chrome reacts with the nitrogen of the ceramic to produce CrxNy and join. Also, chrome Cote queuing junction plate, nickel bonding plate
It prevents the resin from penetrating into the ceramics side to form a compound, and improves the joint strength and heat resistance of the joint.

[0007]

An embodiment of the present invention will be described with reference to the drawings.
For example, in order to bond silicon nitride ceramics (Si3N4) to each other, as shown in FIG. 1, a chromium (Ni) plate having a thickness of 0.2 mm, which is a ductile metal, is plated between the ceramics 1, 1 by chromium plating or Chrome (Cr) by IP method or vapor deposition method
Coated bonding plates 2 and 2 are arranged with the chrome layer facing the ceramics 1 side, and these are pressed at 0.53 Kg / mm ² and 1100 in a vacuum of 5 × 10 ^-5 Torr. Heat above ℃
Hold for 20 minutes. According to the above conditions, the thickness of the chrome layer,
As a result of an experiment conducted by changing the heating temperature, a high bonding strength was obtained as shown in Examples 1 and 2 of the attached table. Attached table `` 2.98μm Cr-0.2m
"mNi" indicates a 0.28-mm-thick nickel plate subjected to 2.98 µm chrome coating as the joint plate 2 in Fig. 1, and the joint strength MPa indicates the strength of the four-point bending test.

The chrome layer comes into contact with the ceramic to metallize its surface, and at the same time, the chrome reacts with the nitrogen of the ceramic to produce CrxNy to bond. Further, the chromium coating of the joint plate prevents nickel of the joint plate from penetrating into the ceramics side to form a Ni-Si compound, and the joint strength and heat resistance of the joint portion are improved. As described above, by using nickel instead of silver as the brazing material, the heat resistance of the joint is improved, and the metallization and joining of the ceramics can be performed in one step, thus improving the work efficiency.
The above-mentioned joining conditions are such that the degree of vacuum is changed from 10 ^-4 to 10 ^-5 Torr, the applied pressure is changed from 0.1 to 6 kg / mm ² , the heating temperature is changed from 1000 to 1200 ° C, and the holding time is changed from 3 to 60 minutes. The average bonding strength and heat resistance of the ceramics do not substantially change.

Another embodiment is shown in FIG. A molybdenum (Mo) plate 3, which is a low thermal expansion material, is interposed between the bonding plates 2 and 2, and is similarly heated to 1000 to 1200 ° C. in a vacuum atmosphere, and is held under pressure for 1 to 60 minutes, Ceramics 1
At the same time as forming a chromium metallized layer on the surface of the ceramics, the ceramics are bonded together. In the test results,
High bonding strength was obtained under the conditions as shown in Example 3 of the attached table.

Next, another embodiment is shown in FIG. A copper (Cu) plate 4, which is a soft metal, is interposed between the bonding plates 2 and 2 to reduce thermal stress, and similarly, heating and pressing are performed in a vacuum atmosphere to bond the ceramics together.
As a result of the test, the bonding strength shown in Examples 4 and 5 of the attached table was obtained.

FIG. 4 shows a thermal stress relaxation material using a molybdenum plate 3 and two copper plates 4. The joining conditions are the same as those in the above-mentioned embodiment. In Example 6 of the attached table,
FIG. 1 shows the result of a test when a nickel plate having a thickness of 0.3 mm is interposed between the joining plates 2 and 2.

In Example 7 of the attached table, the joining plates 2 and 2 in FIG.
Between low thermal expansion alloys (Ni 29%, Co 17%, Mn, Si, M) having a thermal expansion coefficient relatively close to that of 0.1 mm thick Si3N4.
All the g, Zr, C, Al, and Ti are 1% or less, the balance Fe) shows the results of the test when a plate is interposed, and high bonding strength was obtained.

[0013]

[0014]

EFFECTS OF THE INVENTION The present invention has an effect that the joint strength and heat resistance of the joint portion between the ceramics are improved, and the metallization and the jointing of the ceramics can be performed in one step, so that the working efficiency can be improved.

[Brief description of drawings]

FIG. 1 is an explanatory view of an embodiment of the method of the present invention.

FIG. 2 is an explanatory view of another embodiment of the method of the present invention.

FIG. 3 is an explanatory view of another embodiment of the method of the present invention.

FIG. 4 is an explanatory view of another embodiment of the method of the present invention.

[Explanation of symbols]

 1 Ceramics 2 Chrome Coating Nickel Plate 3 Molybdenum Plate 4 Copper Plate

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-60-90878 (JP, A) JP-A-61-137688 (JP, A) JP-A-63-274677 (JP, A) JP-A-63- 230576 (JP, A) JP-A-4-26571 (JP, A)

Claims (1)

(57) [Claims] 1. A bonding plate made of a nickel plate on which a chrome thin film layer is formed is provided between the ceramics and the ceramics so that the chrome thin film layer faces both of the ceramics and heated and heated in a predetermined vacuum state. A method for joining ceramics to each other characterized by applying pressure.