JPH0445277B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a brazing material (hereinafter referred to as "brazing material") for joining ceramics to ceramics, ceramics to metals, and metals to metals. (Prior art and its problems) Conventional methods for joining ceramics and metals include the oxidation solder method, the Telefunken method, and the active metal method. The active metal method uses very active metals such as Ti and Zr and Ni and Cr, which form alloys with these with relatively low melting points.
In this method, a brazing filler metal having a eutectic composition is inserted between the ceramic and the metal, and the bonding is performed in vacuum or in an inert gas. By the way, the eutectic temperature of the metal is Cr-Ti34
Since the temperature is 880°C by weight and 955°C by 24.5% by weight of Ti-Ni, it is necessary to bond at a high temperature. Furthermore, since bonding is performed at high temperatures, thermal expansion also increases. As described above, the brazing temperature of the brazing filler metal used in the conventional active metal method is a high temperature of 900° C. or higher, which has caused problems such as energy loss, softening of the metal base material, and high coefficient of thermal expansion. (Object of the Invention) The present invention was made to solve the above-mentioned problems, and an object of the present invention is to provide a brazing material that can be used at a low brazing temperature and that can increase the strength of a brazed joint. (Structure of the Invention) One of the brazing materials of the present invention is composed of 47.6 to 84.0% by weight of Ag, 4.8 to 9% by weight of at least one of Zr and Hf, and the remainder Cu. Another brazing material of the present invention includes 47.6 to 84.0% by weight of Ag, 4.8 to 9% by weight of at least one of Zr and Hf,
At least one of In and Sn 0.4 to 20% by weight, balance Cu
It consists of The reason why at least one of Zr and Hf is 4.8 to 9% by weight in the brazing filler metal of the present invention is to increase the strength of the brazed joint.If it is less than 4.8% by weight, the wettability to ceramics is poor; This is because the strength of the brazed joint is poor; if the content exceeds 9% by weight, the melting point of the solder increases, and at least one of Zr and Hf remains in large amounts in the solder, which increases the amount of brittle intermetallic compounds and reduces the strength of the brazed joint. is inferior. At least one of Zr and Hf, Ag, Cu, In,
The reason for including Sn is to lower the melting point of the brazing material and to soften the stress caused by thermal expansion that acts on the interface after brazing. The brazing filler metal of the present invention also contains a large amount of Ag because at least one of Zr and Hf in the brazing material moves to the interface of the base metal and wets the ceramic during brazing.
Ag−Cu−In−Sn forms the center. Therefore, the soft Ag-Cu-In-Sn becomes a cushion, improving the strength and preventing the ceramic from cracking. (Example) Specific examples of the brazing filler metal of the present invention will be described together with conventional examples. The brazing filler metals of Examples 1 to 6 having the compositions shown in Table 1 below were melted by high frequency flotation melting, cast into copper molds, and cut into 0.1 mm plates. . The filler metal in Conventional Example 1 is Ti plate, Cu
The brazing material of Conventional Example 2 is a Ti plate and a Ti plate.
Three sheets, a Ni plate and a Ti plate, are joined by hot rolling to form a 0.1 mm plate. (Margin below)

【table】

[Table] Each of the brazing filler metals of Examples 1 to 6 and Conventional Examples 1 and 2 was cut or punched into predetermined dimensions, and used to prepare ceramics and ceramics, and ceramics and Fe-Ni42% alloy by weight. I performed brazing with. The brazing temperature at that time was measured, and the brazed joints were subjected to shear tests and crack tests, and the results shown in Table 2 below were obtained.

【table】

[Table] As is clear from Table 2 above, the brazing fillers of Examples 1 to 6 have lower brazing temperatures and significantly higher brazing strength than the brazing fillers of Conventional Examples 1 and 2. It can be seen that the objective strength is also high. (Effects of the Invention) As described above, the brazing material of the present invention has a low brazing temperature, so it can reduce energy loss during brazing, suppress the softening of the metal base material, and further reduce the coefficient of thermal expansion. It can relieve thermal stress. Furthermore, it has the effect of increasing the brazing strength and also increasing the mechanical strength of the brazed joint, so it can be said to be an epoch-making product that can replace conventional brazing materials.

Claims (1)

[Claims] 1. A brazing material comprising 47.6 to 84.0% by weight of Ag, 4.8 to 9% by weight of at least one of Zr and Hf, and the balance Cu. 2 47.6 to 84.0% by weight of Ag, 4.8 to 9% by weight of at least one of Zr and Hf, 0.4% of at least one of In and Sn
Brazing material consisting of ~20% by weight, balance Cu.