JPS6197174A - Diffusion bonding method for ceramics and metals - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to an improvement in a method of diffusion bonding between ceramics and metal, and can be used for manufacturing ceramic products.

(Prior Art) Among the bonding methods for ceramics and metals, the diffusion bonding method is a very effective method because it can economically obtain a strong bonded body, so there have been many applications for this method. It has become publicly known in Japanese Patent Application Laid-Open Nos. 58-125678, 185180-1980, and 185788-1988 from applications filed by individuals.

By the way, when performing such diffusion bonding, it goes without saying that a sufficient bond cannot be obtained unless the surfaces to be bonded are cleaned. Usually, only degreasing is required, such as wiping with acetone or ultrasonic cleaning in acetone. After this, diffusion bonding was performed at a high temperature close to the melting point of the base metal or insert metal used for bonding.

(Problem to be solved) By the way, diffusion bonding requires atmosphere adjustment, pressurization, and heating, and care must be taken not to have a thermal effect on the structure of the bonded base materials, and when joining dissimilar base materials. From the viewpoint of reducing residual stress due to heat at the bonding interface and economically performing bonding, it is desirable that the heating temperature be as low as possible. Nevertheless, there is a problem in that a sufficient bonded body cannot be obtained unless diffusion bonding is performed under high-temperature heating as described above.

(Means for solving the problem) By the way, a requirement for sufficient bonding is that the surface to be bonded must be clean, and if this cleaning is done sufficiently, there will be no need for high-temperature heating. I came up with this idea. Therefore, in the present invention, when bonding ceramics and metals, the surface of the metal to be bonded to the ceramics is cleaned by etching or etching, and then diffusion bonding is performed.

(Operation) Etching provides cleaning of the metal surface and exposure of fresh metal that cannot be obtained by other methods. This activates the metal surface, improving bonding properties and
Moreover, high-temperature heating is no longer required.

(Example) A silicon carbide piece 1 with a diameter of 10 mm and a thickness of 5 m and a piece of pure aluminum (A10
50) The piece was ultrasonically cleaned in acetone for 10 minutes and then plasma etched in argon gas for 30 minutes. Then, these treated surfaces are concentrically superimposed as bonding surfaces as shown in Figures 1 and 2, and approximately 8X10To
After heating at 350°C and applying pressure for 60 minutes in a vacuum of 7'Co, and cooling to room temperature, the shear strength was approximately 0.5~lkf. A good bonded body was obtained.The shear strength was
500℃~550℃ without plasma etching
Corresponds to that during heating.

For comparison, when diffusion bonding was performed in the same manner as described above except for plasma etching treatment, the ceramic and metal were not bonded and were completely separated at the interface.

(Other Examples) As another example, the ceramics used include silicon carbide, non-oxide ceramics such as silicon nitride, and oxide ceramics such as alumina, I-sialon, zirconia, and -magnesia. be able to. Further, the ceramic surface may be metallized by vapor deposition or other methods.

Furthermore, the metal is not limited to aluminum, its alloys, and composite materials, and may be iron-based metals, titanium, copper, nickel, alloys thereof, and the like. and,
It is applicable not only when these metals are used as base metals but also when they are used as insert metals.

Furthermore, etching is not limited to plasma etching, and may be chemical etching or mechanical etching, and prior to these etchings, acetone wiping or ultrasonic cleaning in acetone may be performed in advance. It is also possible to perform etching alone.

However, in the above-mentioned embodiments, the ceramic side is also etched, but originally, etching only needs to be carried out on the metal. Such etching may be performed when performing bonding methods of ceramics and metals other than diffusion bonding, such as brazing or pressure welding methods other than diffusion bonding, but these etchings are performed in the atmosphere. As for bonding, no great effect can be expected.

The heating temperature is not limited to 350°C as in the above example; 350°C is a relatively low temperature at which bonding can be achieved, and in order to obtain greater shear strength, heating at a higher temperature is required. All you have to do is

Note that this heating temperature is determined experimentally depending on the type of metal to be joined and the degree of etching.

(Effects of the Invention) As described above, in the diffusion bonding of ceramics and metals, the present invention enables strong bonding between ceramics and metals at low heating temperatures by engineering the bonding surfaces of the metals. This has a remarkable effect that can be obtained by diffusion bonding.

[Brief explanation of the drawing]

The drawings show an embodiment of the invention, with FIG. 1 being a plan view and FIG. 2 being a side view. In FIGS. 1 and 2, 1 is a silicon carbide piece (ceramics), and 2 is an aluminum piece (metal).

Claims (6)

[Claims] (1) In the diffusion bonding method of ceramics and metal,
The diffusion bonding method includes etching a surface of the metal to be bonded to the ceramic, and then bonding the ceramic and the metal. (2) The diffusion bonding method according to claim 1, wherein the metal is a base metal to be bonded to the ceramic. (3) The diffusion bonding method according to claim 1, wherein the metal is an insert metal interposed between the ceramic and the base metal. (4) The diffusion bonding method according to claim 1, wherein the etching is plasma etching. (5) The diffusion bonding method according to claim 1, wherein the etching is chemical etching. (6) The diffusion bonding method according to claim 1, wherein the etching is mechanical etching.