JPH11213946A - Component for brazing electrode and brazing electrode for discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a component for a brazing electrode and a brazing electrode for a discharge lamp for obtaining a metal vapor discharge lamp capable of being brazed to a pipe-shaped support its self and a W electrode with high joining strength and less weakness of a base material, having a stable joining part, suppressing the scattering of an inside metal halide, stabilizing the remaining amount within the discharge lamp, and hardly generating minute leaks after sealing. SOLUTION: A component 1 for a brazing electrode is formed in a pipe shape in such a way that a plate material made of Mo or a Mo alloy is formed in a cylindrical shape by bending, the end parts in the circumferential direction are butted or piled up each other, and brazed with a first brazing material 5. An electrode 12 made of a rod-shaped W or W alloy is brazed with a second brazing material 6 to the inside of the joining part of the component 1 for the pipe-shaped brazing electrode for a discharge lamp. These first and second brazing materials 5, 6 are prepared by adding 1.4-3.0 wt.% boron (B) to a Ru-Mo eutectic alloy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refractory metal electrode used for a metal vapor discharge lamp such as a metal halide lamp and a sodium lamp.

[0002]

2. Description of the Related Art Conventionally, metal vapor discharge lamps such as metal halide lamps and sodium lamps are known. This metal vapor discharge lamp is one in which a metal halide, amalgam, or the like is sealed, the light color is changed by the emission spectrum of these metals, and the efficiency and color rendering are improved.

FIG. 5 is a schematic sectional view showing the structure of a conventional metal halide lamp. Referring to FIG. 5, the metal discharge lamp 50 has a rod-shaped W electrode 12 having a W coil 11 at one end, which is a discharge electrode, and a molybdenum (Mo) foil 13.
Are respectively connected to the Mo leads 14 by resistance welding or the like. This connection part is sealed at the end face of the alumina glass tube 15 constituting the discharge lamp light emitting part. After assembling these parts, the metal halide is put into a discharge lamp light emitting part made of alumina glass, and heated and sealed at about 1500 ° C.

However, since the alumina glass tube 15 has a metal halide inlet, it is necessary to heat the alumina glass tube 15 during sealing. At that time, the metal halide charged inside evaporates and leaks during heating.
Further, since the leak amount is unstable, it is difficult to keep the remaining amount in the discharge lamp constant.

[0005] In order to improve the drawback, for example, Japanese Patent Application Laid-Open No. Hei 7-176296 (hereinafter referred to as "prior art 1") discloses a structure in which the Mo foil 13 is replaced with a support made of a platinum pipe. In this prior art 1,
This is a structure in which both ends of a platinum pipe protrude into and out of the discharge lamp main body and are sealed on the outer peripheral surface. After encapsulation, a metal halide is introduced through a platinum pipe, and the platinum pipe is heated and sealed. In this case, since the alumina glass part is not heated, the scattering of the metal halide inside is small and the remaining amount in the discharge lamp is stabilized.

However, the platinum pipe has a low strength and a thermal expansion coefficient of about 11 × 10 ^{−6, which} is larger than that of alumina glass of about 8 × 10 ^−6. And a minute gap is easily generated between the alumina glass tube 15. Therefore, there is a problem that the probability of occurrence of a minute leak is high.

On the other hand, it has been considered that Mo is formed into a pipe shape having a high temperature strength and a relatively high thermal expansion coefficient relatively close to that of alumina glass, and is used instead of a platinum pipe.

In general, a Mo pipe is formed into a raw pipe by forming a through hole in a rod material by a gun drill or the like, and a vibrator of a required size is manufactured by pipe drawing and cutting. Further, depending on the size, it is manufactured by cutting a ring shape from a plate processed by rolling or forging, or pressing and sintering into a ring shape by powder metallurgy.

[0009]

SUMMARY OF THE INVENTION However, Mo
Is a difficult-to-work metal, and it is difficult to work at a high processing rate during pipe drawing. Therefore, many die drawing steps are required up to a predetermined size, and defects such as cracks occur and the yield is poor. There is a problem.

Further, in the processing of forming a pipe from the bar and the plate, there are many cases where a portion removed by processing is more than a part of a product. That is, the yield is extremely poor, the amount of resources and energy used is large, and this is a factor of high cost.

Further, in the method of cutting from a plate material, the thickness of the plate material is limited to its length, and it is difficult to manufacture a long product.

[0012] On the other hand, the Mo sintered product has an advantage that the processing amount is greatly reduced, but there is a concern about strength because the density is not sufficiently increased.

Therefore, there is a strong demand for a method of forming a pipe-shaped member by joining both ends of a bent plate.

[0014] Even when the W electrode and the end face of the Mo support are joined together, there is a strong demand for a joining method which does not cause a decrease in strength. Therefore, the joining method of W and Mo,
That is, the method of joining the W electrode and the Mo pipe becomes a problem.

Normally, W and Mo are joined by resistance welding. However, both W and Mo are refractory metals and have good electrical and thermal conductivity, so that the weldability is poor and the joining strength is unstable. There is.

Therefore, welding methods that can be applied to refractory metals such as W and Mo include fusion welding using an arc, TIG, laser, electron beam, etc., brazing welding,
Examples include diffusion bonding, mechanical bonding such as riveting and bolting.

Among these, fusion welding heats a portion of the base material to be welded, and produces a molten metal by melting only the base material or the base material and the filler metal, and solidifies and joins the molten metal. It is widely used in the fabrication of structures, mainly iron-based metals. However, since the base material needs to be dissolved by the fusion welding method, it is essential to heat the base material to a temperature higher than the melting point of the W material. In addition, since the melting and solidification of the base material accompany the structural change, that is, recrystallization and its coarsening are unavoidable, the residual stress and the structural change cause embrittlement near the weld joint and a decrease in strength. Therefore, it is particularly difficult to apply to hard-to-melt metals such as W and Mo, which are remarkably embrittled by crystal grain coarsening accompanying melting and solidification.
In diffusion bonding between Mo, bonding becomes possible only at a recrystallization temperature or higher, so that embrittlement occurs due to coarsening of crystal grains. Therefore, use of an insert material such as Ni foil has been studied to reduce the joining temperature. However, in that case, depending on the use temperature, an intermetallic compound is formed and embrittlement occurs. For example, about 1000 ° C for Ni / W
Ni-W intermetallic compound at about 800 ° C for Ni / Mo
Produces a Ni-Mo intermetallic compound.

Although mechanical fastening with rivets or bolts has been used for a long time and is stable in strength, it is difficult to apply to small parts and there is a problem in the adhesion of the joining surfaces.

In addition, brazing does not melt the base material,
This is a method in which a filler metal (brazing material) having a melting point lower than that of the base material is melted, and the molten metal is spread over the gap between the joining surfaces by utilizing the capillary phenomenon. Therefore, there are advantages such as crystal grain coarsening due to melting and solidification and embrittlement due to formation of intermetallic compounds do not occur, and thermal stress can be suppressed due to low construction temperature, and there is no structural change in the base metal. is there. Furthermore, it is suitable for materials that require high energy for melting the base material, such as hardly meltable metals, or for materials that are liable to crack during solidification.

For example, as a brazing material for W and Mo,
Silver brazing at low temperature (800 ° C or less), Ru- at high temperature.
Mo eutectic alloy brazing material is used. Silver brazing cannot be used at high temperatures because of its low brazing temperature.
In addition, the use of a material having a melting point or lower has a further lowering of the softening temperature, so that there is a great concern that the strength is reduced.

On the other hand, in the case of the Ru—Mo eutectic alloy brazing material, there is little concern about a decrease in strength at high temperatures, but the brazing temperature is 2%.
Since the temperature is as high as 000 ° C., embrittlement of the W and Mo base materials becomes a problem, and there is a major problem of strength reduction.
A brazing material having a high bonding strength is desirable.

Therefore, one technical problem of the present invention is that a pipe-shaped support which has excellent bonding strength and is less likely to cause brittleness of a base material can be manufactured by brazing, and the pipe-shaped support and the W electrode are also brazed. Accordingly, it is an object of the present invention to provide a brazing electrode component and a brazing electrode for a discharge lamp using the same, which can be joined and have a stable joint.

Further, another technical problem of the present invention is that
By applying the above brazing electrode parts to a metal vapor discharge lamp, it is possible to suppress the scattering of metal halide inside and stabilize the remaining amount in the discharge lamp, and to use a brazing electrode part using the same. An object of the present invention is to provide a brazing electrode for an electric lamp.

Still another technical problem of the present invention is that an alumina glass used as luminescent light and a pipe-shaped support have relatively close thermal expansion coefficients, and the pipe-shaped support has a high high-temperature strength and is difficult to seal. It is an object of the present invention to provide a brazing electrode component used for a metal vapor discharge lamp in which a small leak after sealing is less likely to occur because of little distortion, and a brazing electrode for a discharge lamp using the same.

[0025]

According to the present invention, a plate made of Mo or Mo alloy is formed into a tubular shape by bending, and its circumferential ends are abutted or overlapped to form a first brazing filler metal. A brazing electrode part characterized by being formed into a pipe by joining by brazing using a material is obtained.

According to the present invention, in the brazing electrode component, the plate is made of lanthanum or lanthanum oxide in an amount of 0.1 to less than 1.0%, and the remainder is molybdenum. A component for a brazing electrode is obtained, which has crystal grains exhibiting an interlocking structure that are elongated in a certain direction and recrystallized.

Further, according to the present invention, in any one of the brazing electrode parts, the first brazing material is made of Ru-
Boron (B) was added to the Mo eutectic alloy from 1.4% by weight to 3.0% by weight.
A part for a brazing electrode is obtained, which is substantially composed of the one added by weight%.

Further, according to the present invention, any one of the brazing electrode parts described above is used, and a rod-shaped electrode made of W or W alloy is provided inside the joint of the pipe-shaped brazing electrode part. A brazing electrode for a discharge lamp characterized by being joined by brazing using a brazing material is obtained.

According to the present invention, in the brazing electrode for a discharge lamp, the second brazing material and the first brazing material are made of the same material and are formed in the pipe shape. It is possible to obtain a brazing electrode for a discharge lamp, which is characterized in that the rod-shaped electrode made of W or W alloy is joined to the pipe at the same time.

Further, according to the present invention, in any one of the brazing electrodes for a discharge lamp, the first and second brazing materials are each made of Ru-Mo eutectic alloy containing 1.4 parts of boron (B). Thus, a brazing electrode for a discharge lamp is obtained, which is substantially composed of an addition of from 3.0% by weight to 3.0% by weight.

According to the present invention, in the component for a brazing electrode for a discharge lamp, the second brazing material may include the first brazing material.
Thus, a brazing electrode for a discharge lamp characterized by having a lower melting point than the brazing material is obtained.

Further, according to the present invention, in the brazing electrode for a discharge lamp, the first and second brazing materials are each composed of a Ru—Mo eutectic alloy containing boron (B) in an amount of 1.4% by weight. 3.0% by weight.
A brazing electrode for a discharge lamp, characterized in that the content of boron (B) in the brazing material is smaller than the content of boron (B) in the second brazing material.

[0033]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of a metal vapor discharge lamp to which a brazing electrode component according to an embodiment of the present invention is applied. FIG. 1 shows only one side of the electrode,
An example is shown in which a brazing electrode part, which is a pipe-shaped support, is applied, but it may be used for both electrode parts as needed. Referring to FIG. 1, a metal vapor discharge lamp 10 is provided with W electrodes 12, 12 which are discharge electrodes having W coils 11 at opposite ends opposite to each other. The W electrode 12 at one end is connected to the Mo lead 1 by resistance welding or the like via a brazing electrode part 1 which is a pipe-like support for the W electrode 12.
4 is connected. On the other hand, the W electrode 12 at the other end is connected to the Mo lead 14 via the Mo foil 13 by resistance welding or the like, as in the related art.

These discharge electrodes are sealed at the end face of an alumina glass tube 15 constituting a discharge light emitting portion. After assembling these parts, the halogen metal fill 16 is put into the alumina glass tube 15 and heated to about 1500 ° C. for heat sealing.

FIG. 2 is a schematic structural view mainly showing a brazing electrode part 1 of the metal vapor discharge lamp of FIG. 1, wherein FIG.
(B) is a cross-sectional view. With reference to FIGS. 2A and 2B, the brazing electrode component 1 is configured such that circumferential end surfaces of a cylindrical molybdenum (Mo) base material 7 formed by bending are joined to a first brazing material 5. And one end of the W electrode 12 is also simultaneously joined by the second brazing material 6. As described above, by applying the brazing electrode component 1 to a metal vapor discharge lamp, scattering of the metal halide inside can be suppressed, and the remaining amount in the discharge lamp can be stabilized. Furthermore, since the thermal expansion coefficient of the alumina glass and the Mo pipe is relatively close, and the high temperature strength of the Mo pipe is high and the distortion at the time of sealing is small, it is possible to obtain a metal vapor discharge lamp in which a minute leak after sealing is hardly generated. .

As a high-temperature brazing filler metal for W and Mo, for example, a Ru-Mo eutectic alloy brazing filler alloy exhibiting excellent wettability to W and Mo is known, and this brazing filler metal has a melting point. Since the temperature is as high as 1955 ° C., there are many problems in strength reduction and construction due to embrittlement of W and Mo base materials.

On the other hand, the melting points of the brazing materials 5 and 6 according to the embodiment of the present invention are adjusted without impairing the wettability by adding an appropriate amount of boron (B) to the Ru—Mo eutectic alloy brazing material. be able to.

FIG. 3 shows a Ru-Mo eutectic alloy (43% Ru-
It is a figure which shows the melting point change with respect to the addition amount of boron (B) in the brazing material which consists of 57% Mo). As shown in FIG. 3, the Ru—Mo eutectic alloy has a boron (B) addition amount of 1.5%.
From 1900 ° C to 153%
The melting point is lower at 0 ° C. In the embodiment of the present invention, the composition range of the base Ru-Mo brazing material can be 33.5 to 49.5% by weight of Ru. Ru-Mo brazing material is Ru-Mo in this range.
It has a eutectic structure and a eutectic point of 43% by weight Ru.
-57% by weight Mo is desirable.

Further, the brazing temperature may be set at about 30 ° C. to 50 ° C. higher than the melting point, but may be changed depending on the work size and the heating method.

As a method for applying the brazing material, a method of applying a paste in an organic solvent to form a paste is simple. However, the brazing material may be formed into a thin plate or a rod by pressing, rolling or extrusion. At the time of molding, a binder such as paraffin may be mixed as necessary. Here, the binder may be one used for forming ordinary W, Mo or cemented carbide, and the same applies to the conditions for removing the binder.

By joining the butted or overlapped portions of the bent molybdenum material using the above brazing material, a pipe-shaped member having excellent joining strength can be manufactured.

Here, the bent shape may be formed into a gutter shape, a C-shaped shape or the like by hot bending, pressing or forming rolls.

Alternatively, a gap may be left in the C-shaped joint, or a cut may be made in the C-shaped joint, and the W electrode 12 may be set in that portion and brazed at the same time.

Since the heating temperature at the time of sealing the alumina glass tube 15 is about 1500 ° C., it is necessary to use a brazing material having a melting point at least higher than that, preferably 1600 ° C. or higher.

In the above brazing material, since the melting point can be selected in the same manner as that shown in FIG. 3, after the brazing electrode part 1 is manufactured by brazing using the first brazing material, the melting temperature is further increased. By brazing using a low brazing second brazing material,
It is also possible to braze another member such as the W electrode 12 without melting the brazing portion of the brazing electrode component 1.

In general, pure molybdenum is selected as the Mo base material in view of its workability and cost, but its recrystallization temperature is as low as about 1000 ° C. Further, as a molybdenum material used at a high temperature, for example, 0.5% T
TZ containing i, 0.07% Zr, and 0.05% C
M (product name of U.S.A. Climax) is known, but also in TZM, the recrystallization temperature is 1300-1000.
It is only 1500 ° C. Therefore, high-temperature deformation and embrittlement occur due to heating at about 1500 ° C. when sealing the alumina glass.
Problems such as electrode displacement and dropping are likely to occur.

On the other hand, as shown in Japanese Patent Publication No. 2-38659, molybdenum containing lanthanum is a molybdenum material having excellent workability and high temperature deformation resistance even after a recrystallization temperature. This molybdenum containing lanthanum is
Workability having crystalline particles exhibiting an interlocking structure, consisting of lanthanum or lanthanum oxide in an amount of 0.1 to less than 1.0% by weight and molybdenum with the balance being elongated in a certain direction and recrystallized. And a molybdenum alloy having excellent high-temperature deformation resistance. By using this lanthanum-containing molybdenum as a material, a melting point of 1500
Even when a brazing material having a temperature of not less than ℃ is used, no embrittlement occurs, and the amount of deformation at the time of use at a high temperature can be reduced as compared with a case where pure molybdenum is used as a material.

In the embodiment of the present invention, when a brazing treatment is performed using the above-described brazing material, a Ru—Mo eutectic alloy brazing material conventionally used as a W and Mo high-temperature brazing material is used. Since the brazing temperature can be reduced compared to that of pipes, it is possible to manufacture a pipe-shaped support made of molybdenum, which is less likely to become brittle, and has high high-temperature strength, by brazing, thereby improving the yield compared to pipe drawing. .

Further, the pipe-shaped support and the W electrode can be joined by brazing, and a brazing electrode component having a stable joint can be provided.

In the above description, the cross-sectional shape of the base material of the brazing electrode part 1 is C-shaped, but, for example, it overlaps a part of the cross-section as shown in FIGS. 4 (a) and 4 (b). The same effect as the C-shaped Mo base material can be obtained with the Mo base material 2 having a wound shape or the Mo base material 3 having an end face bent inward.

Next, a specific example of the production of the brazing electrode for a discharge lamp according to the embodiment of the present invention will be described.

Example 1 As shown in FIGS. 2 (a) and 2 (b), a sheet thickness of 0.1 mm. 20mm wide, Japanese Patent Publication No. 2-3865
A lanthanum-containing molybdenum tape similar to that shown in JP-A No. 9-2006 is used with a multiaxial forming machine to have an outer diameter of 1.6.
It was formed into a C-shaped cross section of 1 mm and cut to obtain a Mo base material 7 for brazing. The melting point is about 4900% by weight of Ru-56.
After applying the brazing material 5 made of 2% by weight Mo-1.4% by weight B into a paste with a binder, the misalignment at the time of heating is removed by a jig, and the brazing material is removed in a vacuum furnace at a rate of 15% per minute. The temperature was raised to 1950 ° C at a rate of
After holding for a minute, the pipe was gradually cooled to complete the joining of the pipes.
A brazing electrode part 1 as shown in (a) and (b) was obtained. After this joining process, it was confirmed by visual inspection that the brazing material sufficiently flowed into the gaps of the Mo base material 7, no voids existed, and a very good joining state was obtained.

Thereafter, the melting point is about 1600 ° C. in a range of 8 mm from one end face of the W wire having a diameter of 0.5 mm and a length of 16 mm at the abutting portion of the C-shaped peripheral end of the brazing base material 41. After applying a brazing material 6 in which a brazing material powder consisting of 8 wt% Ru-55.4 wt% Mo-2.8 wt% B was made into a paste with a binder, a W line for the W electrode 12 was projected and the length was protruded. At a position of 8 mm, the portion where the brazing material 6 was applied was set so as to be in contact with the Mo base material 7 for brazing, and further displacement and deformation were prevented with a jig, and the temperature was raised at 15 ° C./min in a vacuum furnace. The temperature was raised to 1650 ° C. at a temperature rate and maintained at this temperature for 5 minutes, followed by slow cooling to complete the joining. Even after this joining process, it was confirmed by visual appearance inspection that the brazing material sufficiently flowed into the gap with the base material, that no void existed, and that a very good joining state was obtained. Also, it was confirmed that no change occurred in the brazing portion of the brazing electrode part 1.

About half of the length of the soldering electrode is
Was inserted into one end of an alumina glass tube 15 and sealed.
The other end is connected to a Mo lead 14 via a normal Mo foil 13 and is sealed at an end face of an alumina glass tube 15. Thereafter, a metal halide is introduced through the opening 1a of the brazing electrode, and then a Mo lead 14 having a separately prepared Mo cap 17 is inserted into the opening 1a and brazed and sealed with a commercially available silver braze. The light emitting part 10 of the discharge lamp was obtained. In this case, when the opening 1a of the brazing electrode was sealed, the heating portion was separated from the portion where the metal halide was present, so that evaporation and scattering of the metal halide could be reliably prevented. In addition, since the thermal expansion coefficient of the alumina glass tube 15 and the Mo pipe which is the soldering electrode part 1 is relatively close, and the high temperature strength of the Mo pipe is high and the distortion at the time of sealing is small, a minute leak after sealing is obtained. No occurrence was observed.

(Example 2) As shown in FIGS. 2A and 2B, a Japanese Patent Publication No. 2-3865 having a thickness of 0.1 mm and a width of 20 mm was used.
The lanthanum-containing molybdenum tape disclosed in Japanese Patent No. 9 was formed into a C-shape having an outer diameter of 1.6 mm by a multiaxial forming machine and cut to obtain a Mo base material 7 for brazing. A melting point of about 170 was applied to the end face of the longitudinal straight portion of the Mo base material 7 for brazing.
42.1 wt% Ru-55.7 wt% Mo- at 0 ° C.
After applying the brazing filler metal 5 made of a paste of 2.2 wt% B using a binder, the diameter is 0.5 m.
m, a W wire for a W electrode 12 having a length of 16 mm is protruded, and a portion where the brazing material is applied is set at a position where the length becomes 8 mm, at a brazing base material butt portion, and a speed of 15 ° C./min. The temperature was raised to 1750 ° C. and held at this temperature for 5 minutes, followed by slow cooling to complete the joining.

After the joining process, it was confirmed by visual inspection that the brazing material sufficiently flowed into the gaps between the base materials, that no gaps existed, and that a very good joining state was obtained.

Further, by manufacturing a discharge lamp in the same manner as in Example 1, it was possible to confirm the effect of preventing the metal halide from evaporating and scattering, and the good sealing property with the alumina glass.

[0058]

As described above, according to the present invention, it is possible to manufacture a pipe-shaped support having excellent joining strength and less risk of embrittlement of the base material by brazing, and furthermore, the pipe-shaped support and W The electrodes can also be joined by brazing, so that a brazing electrode component and a brazing electrode for a discharge lamp having a stable joint can be provided.

Further, by applying the brazing electrode part of the present invention to a metal vapor discharge lamp, a discharge lamp capable of suppressing the scattering of metal halide inside and stabilizing the remaining amount in the discharge lamp can be obtained. A brazing electrode component and a brazing electrode for a discharge lamp can be provided.

Further, according to the present invention, since the thermal expansion coefficient of the alumina glass and the Mo pipe is relatively close, and the high temperature strength of the Mo pipe is high and the distortion at the time of sealing is small, a small leak after sealing is generated. It is possible to provide a brazing electrode component and a brazing electrode for a discharge lamp that can provide a metal vapor discharge lamp that is difficult to perform.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a metal vapor discharge lamp using a brazing electrode component according to an embodiment of the present invention.

FIGS. 2A and 2B are schematic sectional views mainly showing the soldering electrode component of FIG. 1, wherein FIG. 2A is a longitudinal sectional view and FIG. 2B is a transverse sectional view.

FIG. 3 is a diagram showing the relationship between the amount of boron (B) added and the melting point of a brazing filler metal made of a Ru—Mo eutectic alloy.

FIGS. 4A and 4B are cross-sectional views showing various examples of a base material of a brazing electrode component according to an embodiment of the present invention.

FIG. 5 is a schematic sectional view showing an example of a conventional metal vapor discharge lamp.

[Explanation of symbols]

 Reference Signs List 1 brazing electrode component 1a opening 2,3,7 Mo base material 5 first brazing material 6 second brazing material 10,50 metal vapor discharge lamp 11 W coil 12 W electrode 13 Mo foil 14 Mo lead 15 alumina Glass tube 16 Halogen metal filling 17 Mo cap

Claims (8)

[Claims] 1. A pipe material formed by bending a plate material made of Mo or Mo alloy into a tubular shape by bending, and abutting or overlapping circumferential ends thereof with each other by brazing using a first brazing material. A part for a brazing electrode, characterized in that it is formed in the form of: 2. The component for a brazing electrode according to claim 1, wherein the plate material is composed of lanthanum or lanthanum oxide in an amount of 0.1% to less than 1.0%, and the remainder is molybdenum, and substantially the same direction. What is claimed is: 1. A component for a soldering electrode, comprising crystal grains exhibiting an interlocking structure which are elongated and recrystallized. 3. The brazing electrode part according to claim 1, wherein the first brazing material is a Ru-Mo eutectic alloy containing 1.4% by weight of boron (B) to 3.0% by weight. A component for a brazing electrode, which is substantially composed of a component added to the solder. 4. A rod-shaped electrode made of W or W alloy and a second brazing material inside the joint of the pipe-shaped brazing electrode part, using the brazing electrode part according to claim 1 or 2. A brazing electrode for a discharge lamp, wherein the electrodes are joined by brazing. 5. The brazing electrode for a discharge lamp according to claim 4, wherein the second brazing material and the first brazing material are made of the same material, and are formed in the pipe shape and the rod shape. A brazing electrode for a discharge lamp, wherein the joining of an electrode made of W or a W alloy to the pipe is performed at the same time. 6. The brazing electrode for a discharge lamp according to claim 4, wherein the first and second brazing materials are each made of Ru.
-Mo (E) eutectic alloy containing boron (B) from 1.4% by weight to 3.0%.
A brazing electrode for a discharge lamp, which is substantially composed of a substance added by weight%. 7. The brazing electrode for a discharge lamp according to claim 4, wherein the second brazing material has a lower melting point than the first brazing material. 8. The brazing electrode for a discharge lamp according to claim 7, wherein the first and second brazing materials are each composed of a Ru-Mo eutectic alloy containing 1.4% by weight of boron (B). The first brazing material has a boron (B) content smaller than the boron (B) content of the second brazing material. Brazing electrode for electric lights.