JPH01154898A - Solder - Google Patents

Abstract

PURPOSE:To obtain the title solder having a low brazing temp. and capable of obtaining high brazed joint strength by kneading a mixture of powdery Ag and Cu and the powdery hydride of a specified metal with a binder. CONSTITUTION:A mixed powdery solder component consisting of 47.6-85.7wt.% powdery Ag, 4.8-19wt.% of at least one kind among Ti hydride, Zr hydride, and Hf hydride, and the balance Cu powder and an org. binder are mixed in 1/3-3/1 ratio to obtain the solder. By using the obtained solder, a ceramic is brazed to a ceramic, a ceramic to a metal, and a metal to a metal with high brazing strength.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a 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 refers to the use of very active metals such as Ti, Zr, etc.
In this method, a brazing filler metal having a eutectic composition of Ni and Cr, which form an alloy with a relatively low melting point, is inserted between the ceramic and the metal, and the bonding is performed in a vacuum or in an inert gas.

Incidentally, the eutectic temperature of the metals is 880°C when Cr and Ti are 34% by weight, and 9°C when Ti-Ni is 24.5% by weight.
Since the temperature is 55°C, bonding must be performed at a high temperature.

Furthermore, since bonding is carried out at high temperatures, thermal expansion also increases.

As described above, the brazing temperature of the brazing material used in the conventional active metal method is a high temperature of 900° C. or higher, which causes problems such as energy loss, softening of the metal base material, and high coefficient of thermal expansion.

To solve this problem, Ag-Cu-(Ti, Zr
, Hf) and other low-temperature brazing fillers have been developed. For joints with complex shapes, powdered solder is often used instead of plate or wire brazing material. However, Ag-Cu-(Ti
, Zr, Hf), the entire atomizing device must be kept in a high vacuum to prevent the active metal from oxidizing, which poses a problem in productivity. In order to solve this problem, a method of mixing Ti, Zr, and Hf powders with Ag powder and Cu powder or Ag and Cu alloy powder has been used. However, with this method, the surfaces of the Ti, Zr, and Hf powders are covered with an oxide film, and the brazing strength is insufficient, so that the powders cannot be used.

(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.

(Means for solving the problem) The brazing filler metal of the present invention contains 47.6 to 85.7% by weight of Ag, T
It consists of a powdery wax component consisting of 4.8 to 19% by weight of at least one of i hydride, Zr hydride, and Hf hydride, and the balance Cu, and a binder component.

The reason why hydrides of Ti5Zr and Hf are used in the brazing material of the present invention is that hydrides are very stable below 600'C and do not form an oxide film, so the surface can be kept clean until just before the solder is stretched. This is because it is effective for brazing properties.

At the brazing temperature, the hydride decomposes and the generated H2
This reacts with trace amounts of oxygen in the brazing atmosphere (usually vacuum or inert), creating the perfect atmosphere for brazing.

In addition, hydrides are produced in the pre-process of producing metal powder, and have the advantage of being inexpensive.

(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 3 with the component compositions shown in Table 1 below are mixtures of Ag powder and Cu powder created by the atomization method and hydrides, and Ag and Cu alloy powder created by the atomization method mixed with hydrogen. It is made by kneading an organic binder into a mixture of chemical compounds. The brazing filler metal of Conventional Example 1.2 is T obtained by decomposing a hydride into Ag powder and Cu powder or Ag and Cu alloy powder, which were also created by the atomization method.
An organic binder is kneaded into a mixture of I powder or Zn powder.

(The following is a blank space) Each brazing filler metal was applied to ceramics and ceramics, and ceramics and Fe-Ni 42 weight% alloy, and joint parts, and brazing was performed. When these brazed joints were subjected to a shear test, the results shown in Table 2 below were obtained.

Table 2 As is clear from Table 2 above, the brazing strength of the brazing fillers of Examples 1 to 3 is significantly higher than that of the brazing fillers of Conventional Examples 1 and 2.

In the above embodiment, the ratio of brazing material to binder is 2=1.
However, the present invention is not limited to this, and from the viewpoint of ease of use as a brazing material, the ratio of the brazing material to the binder is 1.
:3 to 3:1 is a preferable range.

(Effects of the Invention) As described above, the brazing filler metal of the present invention can increase brazing strength and is more cost-effective than conventional brazing filler metals, so it is a revolutionary material that can replace conventional brazing filler metals. It can be said that it is a thing.

Applicant: Tanaka Kikinzoku Kogyo Co., Ltd.

Claims (1)

[Claims] A brazing material consisting of a powdery brazing component consisting of 47.6 to 85.7% by weight of Ag, 4.8 to 19% by weight of at least one of Ti hydride, Zr hydride, and Hf hydride, and the balance Cu, and a binder component.