JPH0238898Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sealed component formed by brazing metal fittings to ceramics.

In general, sealed parts formed by brazing metal fittings to ceramics have better airtightness, heat resistance, and hot insulation than products using conventional hermetic seals with glass and metal structures or plastics. Because of its superior properties such as durability, voltage resistance, and mechanical strength, it is widely used as electronic components such as silicon rectifier envelopes, microwave diode cases, and electron tube envelopes.

FIG. 1 shows an example of such a sealed part, in which one end of a cylindrical metal fitting 2 having the same plate thickness is soldered to a cylindrical ceramic body 1 with a silver solder 3. ing.

In addition, in general, when brazing such a sealed part, the part of the ceramic body 1 to be brazed with the metal fitting 2 is subjected to a metallizing treatment in advance, and then an annular shape is formed between the ceramic body 1 and the metal fitting 2. With the silver solder 3 inserted, for example 800~
This is done by inserting it into a hydrogen atmosphere at 850°C and melting the silver solder 3.

In the sealed part configured in this way, the end face of the metal fitting 2 and the end face of the ceramic body 1 are brazed, so the processing of the ceramic body 1 can be done at low cost, and a relatively inexpensive sealed part can be manufactured. However, the drawback is that the tensile strength between the metal fitting 2 and the ceramic body 1 is low and the mechanical strength of the sealed parts is insufficient.

The present invention has been made in order to eliminate such conventional drawbacks, and is made by brazing the end face of a metal fitting against the metallized surface of ceramics, and making the soldered part of the metal fitting taper in cross section toward the end face. The object of the present invention is to provide a sealed part characterized in that a corner formed by the tapered part and the metallized surface is filled with a brazing material.

Hereinafter, details of the present invention will be described with reference to an embodiment shown in FIGS. 2 and 3.

The sealing part shown in FIG.
The tip 7 at one end of the cylindrical metal fitting 5 is shaped into a tapered trapezoidal shape by turning, etc., as shown in FIG. 3, which shows details of part A shown in FIG. It is formed by machining.

The sealed part constructed as described above is similar to the sealed part shown in FIG. 4 and metal fittings 5
This is done by inserting an annular silver solder 6 between the two and inserting it into a hydrogen atmosphere at, for example, 830° C. to melt the silver solder 6.

However, in the sealed component configured as described above, the tip 7 of the metal fitting 5 is formed in a tapered shape, so that the silver solder 6 melted in the hydrogen atmosphere is The ceramic body 4 and the metal fitting 5 are sealed together with the brazing material filled in the corner formed by the tip part 7 and the metallized surface of the ceramic. The bonding strength is greatly improved compared to the sealed parts shown in FIG.

Further, there is also the effect that sufficient sealing can be obtained even if the amount of silver solder required for sealing is small.

Example: A cylindrical ceramic body 4 with an outer diameter of 16 mm, an inner diameter of 12 mm, and a height of 10 mm is made of a plate having a thickness of 0.3 to 0.3 mm and a tip 7 having an equilateral trapezoidal shape with a top width of 0.2 mm and a bottom width of 0.3 to 0.6 mm. 0.6mm, outer diameter Φ14mm, height 7.5mm metal fitting 5
As shown in FIG. 2, these were brazed with silver solder 6 to obtain a sealed part.

The average tensile strength of the 100 sealed parts thus obtained was 200 kg. In addition, the airtightness of the sealed portion was found to satisfy the airtightness of 3×10 ⁻⁸ cc/sec in a helium airtightness test.

Comparative Example A sealed part having the same structure as the example was obtained except that the tip portion 7 was made straight as shown in FIG.

The average tensile strength of the 100 sealed parts thus obtained was 100 kg.

Another example of the soldered portion of the sealed component of the present invention is shown in FIG. The one shown in FIG. 4 is preferably obtained by punching out a metal fitting obtained by drawing.

As described above, according to the present invention, since the metal fitting is firmly bonded to the ceramic body, it is possible to provide a sealed component with high airtightness and excellent mechanical strength.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a conventional sealing component, FIG. 2 is a longitudinal sectional view showing an embodiment of the sealing component of the present invention, and FIG. 3 is a longitudinal sectional view showing an embodiment of a conventional sealing component. FIG. 4 is a vertical cross-sectional view showing the main parts of part A, and FIG. 4 is a vertical cross-sectional view showing the main parts of the joint of another example of the present invention. 1, 4... Ceramic body, 2, 5... Metal fittings,
3,6...Silver wax.

Claims (1)

[Scope of utility model registration request] The end face of the metal fitting is butted against the metallized surface of the ceramic and soldered, and the soldered part of the metal fitting is formed to have a tapered cross section toward the end face, and the brazing material is applied to the corner formed by the tapered part and the metallized surface. A sealed part characterized by being filled.