JPH01273667A - Brazing method - Google Patents

Abstract

PURPOSE:To save a brazing filler metal and to decrease manhours by disposing a brazing filler metal together with net- or wire-shaped fine metallic wires into the groove of a joing part and penetrating the brazing filler metal into the spacing of the joint part via the capillarity of the fine metallic wire. CONSTITUTION:The fine metallic wires 6 which do not form eutectic crystal with the brazing filler metal 2 are wound like a net or wire to the brazing filler metal 2 and are disposed in the groove 4 of the joint part 3. The brazing filler metal 2 melts and penetrates by the capillarity into the entire area of the spacing between the fine metallic wires 6 when a joining metal 1 is set in a hydrogen furnace and is heated in a vacuum hermetic state. Brazing is thus executed. Since the brazing filler metal 2 is covered by the net- or wire- shaped fine metallic wires 6, the wasteful flow of the brazing filler metal 2 is prevented and the melt thereof accumulates only at the necessary point. The brazing filler metal 2 is thereby saved and the wasteful manhours based on a flow detect are decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a brazing method for vacuum-tightly brazing metals to be joined, which is carried out, for example, in the assembly of vacuum-tight containers such as electron tubes.

[Conventional technology]

When assembling vacuum-tight containers such as electron tubes, two methods are used to ensure vacuum-tightness between metals to be joined: a method in which metals are sandwiched between metals with sketches or metal QIJ tongues, and a method in which metals are brazed in a hydrogen furnace. is taken.

Conventionally, brazing of metals to be joined, such as electron tube containers, has been normally carried out as follows.

As shown in FIGS. 3(a) and (b), a brazing wire 2 is wrapped around the metal 1 near the joint 30, and as shown in FIG. As shown in Fig. 5, the brazing filler metal 2 is placed in the groove 4 provided in the joint 3 of the metal 1, and as shown in Fig. In order to prevent the gap from expanding due to the difference in coefficient of thermal expansion when brazing the inside and outside of the soldering material 1, a method has been adopted in which the soldering material 2 is bound with a wire rod 5 having a higher melting point than the brazing material 2.

[Problem to be solved by the invention]

The above-mentioned conventional method has a problem in that vacuum leakage is likely to occur due to poor flow of the solder when the joint portion becomes larger due to the enlargement of electron tubes and the like.

With the advent of brazing metals whose volume is more than 10 times that of conventional ones, the expansion of gaps due to differences in thermal expansion coefficients, such as when brazing dissimilar metals, cannot be prevented by tying them together with wire rods. As a result of the reduction in machining accuracy that accompanies the increase in size, the flow of solder is asymmetrically blocked at the joints, making vacuum leaks more likely to occur.

Conventionally, vacuum leaks caused by poor solder flow have been repaired by repeatedly inserting a nickel wire into the gap, melting it again, and sealing the leak. Countermeasures have been taken, such as wrapping 5 to 7 times as much brazing material around it and melting it.

The present invention was made to solve the above problems.
The purpose of the present invention is to provide a method that is less likely to cause vacuum leakage due to defective solder flow, can save brazing filler metal, and can significantly reduce man-hours.

[Means to solve the problem]

In the brazing method of the present invention, the brazing material and the thin metal wires that do not produce eutectic are placed in a groove formed in the joint part in a net-like manner, or are wound in a reverse linear pattern. This is a method in which the metal wire sufficiently permeates the entire gap of the joint by capillary action caused by the thin metal wire.

〔Example〕

Below, Figure 1 (a), (b), Figure 2 (a),
The brazing method of the present invention will be explained with reference to (b).

Figure (,) shows the state before melting the filler metal, Figure (b) shows the state after melting the filler metal, and 1, 2, 3.4 are 3.4, 5.6.
The same reference numerals in the figure indicate the same or corresponding parts, and 6 is a thin metal wire knitted and wound around the brazing material wire 2, and the thin metal wire 6 is made of a material that does not form eutectic with the brazing material 2. .

In the groove 4 of the joint part 2, a brazing filler metal 2 in which thin metal wires 6 are knitted and wound in a net shape or twisted in a twisted wire shape is arranged,
When melted in the hydrogen furnace, the brazing filler metal 2 passes through the gaps between the thin metal wires 6 due to capillary action, flows out to the outside of the thin metal wires 6, and fully penetrates into the gap in the joint 2.

Since the brazing filler metal 2 is covered with the thin metal wires 6 knitted in a net shape, there is no wasteful flow, and the molten brazing filler metal 2 that has flowed outside the thin metal wires 6 accumulates in the necessary places and penetrates into the entire gap of the joint 30. I will do it.

〔Effect of the invention〕

As explained above, according to the present invention, unnecessary flow of the brazing filler metal is eliminated, sufficient molten brazing filler metal accumulates in the necessary locations, and the brazing filler metal sufficiently penetrates into the entire gap of the joint, thereby eliminating the problem of poor flow of the filler metal. Vacuum leaks almost never occur, which is highly effective in contributing to savings in brazing filler metal and reduction in man-hours.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing the brazing method of the present invention,
FIG. 3, FIG. 4, FIG. 5, and FIG. 6 are cross-sectional views showing examples of conventional brazing methods. ■...Joining metal, 2...Brazing metal, 3...Joint part,
4...Groove, 6...Thin metal wire. Note that the same reference numerals in the figures indicate the same or corresponding parts. Patent applicant New Japan Radio Co., Ltd. (a) (b) Figure 1 (a) (b) Figure 2

Claims (1)

[Claims] In a brazing method in which metals are brazed in a vacuum-tight state in a hydrogen furnace, the brazing material and thin metal wires that do not produce eutectic are wrapped in a mesh or twisted wire around the grooves provided in the joint. A brazing method characterized by arranging a filler metal and allowing the filler metal to sufficiently permeate the entire gap of the joint by capillary action caused by the thin metal wire.