JPS5935074A - Ceramic sheet - 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 The present invention relates to a ceramic base, that is, a ceramic plate, which can bond a target metal to ceramics.

Conventionally, when a target metal is directly attached to ceramics (e.g. alumina) via a brazing material [7], the coefficients of thermal expansion are different, so residual stress is generated at the interface, which can cause cracks in the ceramic itself. Already known.

Therefore, conventionally, a Kovar gold circle with a coefficient of thermal expansion similar to that of ceramics has been selected and bonded, but this Kovar metal has poor heat resistance and corrosion resistance, so its range of applications is extremely narrow.

The present invention has been made in view of the conventional circumstances, and its purpose is to form a ceramic plate that can be bonded to a desired metal such as stainless steel, which has excellent heat resistance and corrosion resistance and is inexpensive. This is a book that aims to provide.

Embodiments of the present invention will be described below based on the drawings.

The first step is to print a paste of tungsten-molybdenum, molybdenum-manganese, or tungsten alone on a ceramic (for example, an alumina substrate) and bake it at 1400 to 1600°C in a humidified reducing atmosphere to form a paste on the surface of the alumina substrate. A metallizing layer (1) is formed, and a nickel plating layer (4) is further applied as a koji layer.

Next, as a second step, the nickel plating layer (4) is brazed to the K buffer gold (?) via a brazing joint p4.

Loose 135 Gold M (7) Gold F for T, L, stainless steel plates, nickel plates, etc.! A thin plate (thickness: 0.05 mm) is bonded to the nickel plated layer (4) via a solder having a melting temperature of approximately 960°C.

When brazing with alumina substrate and loose metal (2) +i thermal expansion coefficient (ceramics, 75-8
5X10-7/℃, stainless steel 110~185X10-
Although residual stress is generated at the interface due to the difference in V℃),
It is relaxed by the easy elastic deformation of corner metal FF4 (2) and is not transmitted to the metallizing layer (1) and alumina substrate (A), resulting in peeling from the metallizing layer (1) and alumina 7i (i plate). prevents cracking.

In this state, the forming process of the two ceramic plates that join the target gold (14ω), for example [,1 stainless steel (J, B), is completed, and the subsequent process is to form a low melting point brazing metal F↓ (:5b).
By joining the target gold MO3 layered with the nickel plating layer (4) via (silver, copper alloy system), the target metal can be made without any problems. (Step 8) By the way, in the 8th step, there is no problem if the coefficient of thermal expansion of the metal (2) and the target gold JRω) are the same, but if the coefficient of thermal expansion is the same, then the r Although residual stress is generated on the W surface, both metals (A) and (B) are elastically deformed and relaxed, so there is no risk of peeling.

Note that the buffer metal M (2) may be made of panned metal, or may be made of wire braided into a net or fiber shape, as long as it is elastically deformed in response to the residual stress generated at the interface with the alumina substrate (6). It is.

By the way, experiments have shown that even after repeating the rapid cooling and heating cycle from 800°C to room temperature several dozen times on a ceramic plate bonded to gold using the process described above, no abnormality was observed in the bonded area. This has been proven.

In the present invention, as described above, a thin buffer metal is bonded to ceramics laminated with a metallizing layer through a brazing metal, so when brazing through a brazing metal, the ceramic and the buffer metal are bonded together. Although residual stress occurs at the interface due to the difference in coefficient of thermal expansion, the stress is alleviated by the easy elastic deformation of the buffer metal 8, so it is not transmitted to the ceramic, and the ceramic is bonded with the buffer metal to the ceramic surface. A plate can be formed.

Therefore, by joining the target metal to this buffer metal via a brazing metal, a ceramic plate to which the target metal can be easily joined can be provided.

Therefore, the intended purpose can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged cross-sectional view of a ceramic ivy plate according to the present invention. FIG. 2 is a partially enlarged cross-sectional view showing a state in which a target metal is bonded to the ceramic plate. In the figure, (A) is an alumina substrate (re is a metallizing layer ω)
The target metal (2) is the buffer metal (:sa) (
31)) tJ: Brazing Affiliated Patent Applicant Toto Kiki Co., Ltd. Smart

Claims (1)

[Claims] A ceramic plate made by bonding a thin buffer metal to ceramics laminated with a metallized layer via a brazing joint F1.