JP2002361478A - Ag brazing material for joining and brazing method using the same - Google Patents

Abstract

(57) [Summary] [Problem] A solidus temperature and a liquidus temperature are 800 ° C or more.
An Ag brazing material in the range of 900 ° C. is provided. SOLUTION: The Ag brazing material for joining is 1.0% by weight to 1% by weight.
It consists of 0.0% by weight of tin (Sn), 2.5% by weight to 10% by weight of copper (Cu), and the balance being Ag. This Ag
The solidus temperature of the brazing material is 800 ° C. or higher, and the liquidus temperature is 900 ° C. or lower. 6.0% by weight as required
The following manganese (Mn), 0.1 to 2.5% nickel (Ni), or both may be included.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Ag brazing material for joining and a brazing method using the same, and more particularly, it has a solidus temperature of 800.degree. C. or more and a liquidus temperature of 900.degree. The present invention relates to an Ag brazing material which is excellent in bonding properties and has a wide range of application.

[0002]

2. Description of the Related Art Existing A based on Ag-Cu alloy
g brazing material (JIS, Z3261) has a brazing temperature range of 620 ° C to 900 ° C and a solidus temperature of 605 ° C.
C. to 780.degree. Such an Ag-Cu brazing material is widely used for joining metals, for example, joining metals to a ceramic base, joining stainless steel, joining copper (Cu) parts to stainless steel, or joining copper members. Have been.

[0003] Depending on the type of these existing Ag-Cu brazing materials, melting starts at about 605 ° C at low temperatures and starts at 780 ° C at high temperatures.

[0004] In the case where only one joining portion is used, such an existing Ag brazing material is sufficient, but in the case where a plurality of portions are to be joined with time according to the assembling process, the melting points are different. A joining operation is sequentially performed using a plurality of types of brazing materials. Step brazing such brazing,
Or multi-step brazing. Usually, first, using a brazing material with a high melting point, a certain point is joined, and then
Another part is joined using a brazing material having a lower melting point. For example, first, after performing a joining process using a Ni-based brazing material having a melting point of about 1000 ° C., another portion is joined with the above-described Ag-Cu-based brazing material.

[0005] However, step joining using a Ni-based high melting point brazing material is not a problem when the member to be joined is a member having high heat resistance, but a component which is easily softened at the brazing temperature, for example, When a copper (Cu) component is bonded and mounted on a substrate, the base material of the Cu component softens during the brazing operation. Such crystal softening affects device characteristics.

[0006] Therefore, existing A represented by BAg-8
g The brazing material having a melting temperature higher than the melting temperature of the brazing material and having a melting temperature that does not affect the softening of the base material of the member to be joined, in other words, its solidus temperature is 800 ° C. or more and its liquidus temperature is 900 ° C. Although an Ag brazing material having a temperature of not more than C is desired, there is no Ag-Cu brazing material in such a temperature range at present.

[0007] 800 ° C. to 9 ° C.
As a brazing material having a melting temperature range of 00 ° C., a Pd-based brazing material using palladium (Pd) (JIS, Z326)
7) Au-based brazing material using gold (Au) (JIS, Z3
266). However, Pd-based brazing filler metal and Au-based brazing filler metal are extremely expensive in terms of material as compared with Ag brazing filler metal, and there is a problem that the manufacturing cost increases.

Another problem is that the existing Ag brazing material needs to be plated with nickel (Ni) as a pre-treatment when joining a member having a passivation film on its surface such as a stainless member. There is. This is because the surface spreadability or the spreadability of the brazing material cannot be ensured due to the passivation film. That is, if the existing brazing material is used, N
An extra step is required for the i-plating, and the manufacturing cost is increased. Instead of Ni plating, it is conceivable to use an existing Ag brazing material (JIS) premixed with Ni. However, BAg-13a and BAg-21 have a solidus temperature of 800 ° C. or less and a low-temperature brazing material. There is a fear of re-melting when attaching. In addition, BAg-23 has an undesirably high solidus temperature much higher than 900 ° C. and an excessively high brazing temperature.

Still another problem is that the existing Ag
-Among brazing filler metals, brazing temperature ranges do not overlap 2
When step brazing is performed using a combination of Ag brazing materials, for example, those having a solidus temperature of 780 ° C. and those having a liquidus temperature of less than 780 ° C. (eg, BAg-3), a vacuum treatment is performed. There is a problem that can not be done. The low melting point Ag-Cu brazing material is zinc (Zn).
If such a brazing material is used in the bonding process in a vacuum chamber, the inside of the chamber will be contaminated, and the bonding process in the air must be performed in the atmosphere.

In the case of air treatment, the surface of the member to be joined is oxidized, so that the joining is performed while removing the oxide on the surface with a flux. The flux needs to be removed after joining, and the whole article must be cleaned. In this case, the number of joining steps increases, and this also affects environmental issues.

Further, as the objects to be joined are miniaturized, such as electronic parts, there are many cases in which detailed joining is required, and many members requiring hermetic sealing, such as vacuum tubes and vacuum valves. In such airtight brazing or fine brazing, it is necessary to have permeability that can sufficiently enter small gaps.

[0012]

Therefore, the first aspect of the present invention
The purpose of this is that the solidus temperature is 800 ° C or higher and the liquidus temperature is 9
An object of the present invention is to provide a new Ag brazing material having a temperature of 00 ° C. or lower.

A second object of the present invention is to provide an Ag material having sufficient spreadability and permeability that does not require Ni plating on an object to be joined (stainless steel, ceramics, etc.) prior to joining.
To provide brazing filler metal.

A third object of the present invention is to provide an Ag brazing material suitable not only for atmospheric treatment but also for joining treatment in a vacuum chamber.

A fourth object of the present invention is to provide an Ag having a permeability suitable for bonding highly airtight members and fine electronic parts.
To provide brazing filler metal.

Such an Ag brazing material starts melting at about 800 ° C. and completes melting at about 900 ° C. Therefore, by combining with an existing Ag brazing material having a brazing temperature of about 620 ° C. to 800 ° C. or an existing Ni brazing material having a brazing temperature of 1000 ° C. or more, multi-step brazing can be performed a plurality of times. it can.

The novel Ag brazing material of the present invention is intended to be used as a wide range of general-purpose brazing material regardless of the material of the object to be joined.

[0018]

In order to achieve the above object, as a first aspect, a joining Ag brazing material is made of tin (S
n) is 1.0 to 10.0% by weight, and copper (Cu) is 2.5 to
10% by weight, with the balance being silver (Ag).

The solidus temperature of the Ag brazing material is 800 ° C. or more, and the liquidus temperature is 900 ° C. or less. Basically, Ag
The eutectic of Cu and Cu is used, and by setting the composition of Cu in the range of 2.5% by weight to 10% by weight (hereinafter, simply referred to as “%” depending on the case), the Ag brazing material The melting temperature range can be set roughly to a range close to 800 ° C to 900 ° C. By adding Sn to this, the liquidus temperature can be lowered, and the melting temperature of the Ag brazing material can be controlled within the target range of 800 ° C. to 900 ° C. Sn also has the effect of improving the spreadability, and eliminates the need to apply Ni plating as a pretreatment even when the object to be joined has a passivation film on the surface.

If the Cu content is 2.5% or less, it is difficult to control the liquidus temperature of the Ag brazing material to 900 ° C. or less. If the Cu content is 10% or more, the solidus temperature is controlled to 800 ° C. or more. It becomes difficult.

When the amount of Sn is 1.0% or less, the effect of controlling the liquidus temperature of the Ag brazing material to 900 ° C. or less is reduced. If the amount of Sn is 10.0% or more, the fragility increases, and Ag increases.
In this case, the extensibility of the matrix containing Cu and Cu as a main component is impaired.

Such an Ag brazing material is inexpensive, has excellent permeability, and exhibits good bonding strength.

According to a second aspect of the present invention, the Ag brazing material for joining contains 1.0% to 10.0% by weight of tin (Sn).
2.5% to 10% by weight of copper (Cu), and 6.0% by weight.
It is composed of manganese (Mn) of not more than% by weight and the balance being silver (Ag). By adding 6.0% or less of Mn, the strength of the Ag brazing material is improved, and at the same time, the wettability or spreadability with respect to stainless steel and ceramics is improved. When the Mn content is 0.3% to 6.0%,
In particular, it has excellent spreadability. However, since the permeability of the Ag brazing material described above is very good regardless of the Mn content, even if the Mn content is less than 0.3%, A
gExhibits appropriate strength and good bonding properties as a whole brazing material. If the Mn content is 7.5% or more, the brazing filler metal spreads excessively, and the joining portion becomes unstable, which is not preferable.

Depending on the object to be joined, the permeability may be more important than the spreadability of the Ag brazing material. For example, this is a case where a vacuum tube, a vacuum valve, or a fine component that requires vacuum sealing is joined. If the permeability is high,
The brazing material can also penetrate into the fine gaps, and the joining reliability can be improved. In particular, in joining vacuum tubes and fine parts, the strength obtained by adding Mn is not so required, so that low Mn or Mn-free Ag is used.
The brazing material is particularly suitable for use in joining airtight members and fine parts.

In a third aspect of the present invention, the Ag brazing material for joining contains 1.0% to 10.0% by weight of tin (Sn).
2.5% by weight to 10% by weight of copper (Cu);
It consists of nickel (Ni) of not more than% by weight and the balance of silver (Ag). By adding 2.5% by weight or less of nickel (Ni), the wettability or spreadability of the brazed portion and the joining strength can be improved. If the Ni content exceeds 2.5%, the liquidus temperature will increase,
It becomes difficult to control the liquidus temperature of the Ag brazing material to a target of 900 ° C. or lower.

In these Ag brazing materials, part or all of Sn may be replaced with indium (In).
When part or all of Sn is replaced with In, A
g The solidus temperature of the brazing material is 800 ° C or more, and the liquidus temperature is 9
It can be controlled within the range of 00 ° C. or less. At the same time, A
(g) It improves the spreadability of the brazing material or the spreadability of the brazed portion, and contributes to the improvement of the joining property.

When the Ag brazing material contains manganese (Mn), part or all of Mn may be replaced with titanium (Ti). The same effect can be achieved even when part or all of Mn is replaced with Ti, that is, the spreadability is secured and the bonding strength is improved. Even when the portion to be joined is covered with a passivation film, brazing can be performed without the need for nickel plating.

In any of the above-mentioned Ag brazing materials, in the solid state, a matrix containing Ag and Cu as main components having extensibility exists so as to surround a fine precipitation compound containing Sn. Thereby, the vulnerable Sn
Inhibits the generation and propagation of cracks by the compound containing
Workability during brazing material production (ie forging, rolling, drawing)
To improve. At the same time, it protects the bonding layer from weakening after brazing.

When the above-mentioned Sn composition exceeds 10%, the Sn-containing compound precipitated in the Ag-Cu matrix becomes large, and the brazing material itself becomes brittle. Further, since the solidus temperature is excessively lowered, the amount of Sn in the Sn compound precipitated in a solid state is 5% to 60% (weight ratio).
Is a guide.

As described above, Ag and Cu act synergistically on the material properties of the entire brazing filler metal, and particularly affect the solidus temperature, liquidus temperature, and mechanical strength. With this,
Absorbs mechanical shock transmitted to the joint after joining, and suppresses crack generation and propagation. Further, since the Ag-Cu matrix surrounds the precipitated Sn-containing compound, the Ag-Cu matrix also has an effect of preventing the growth of a crack originating from the Sn-containing compound.

In order to adjust the solidus temperature and liquidus temperature, the ratio of Ag / (Ag + Cu) is set to 89.4% to 97.9%.
Preferably it is 5%.

In any of the Ag brazing materials described above,
The production cost is almost the same as that of the conventional Ag brazing material, and the existing A brazing material can be used without using expensive Pd-based brazing material (JIS, Z3267) or Au-based brazing material (JIS, Z3226).
Combination with g brazing material enables multi-step brazing. As a result, the manufacturing cost of the final product can be reduced.

Since the softening of the base material of the members to be joined at the brazing operation temperature can be suppressed, the reliability of the operating characteristics of the final product can be maintained. Since the melting temperature range of the Ag brazing material of the present invention is 800 ° C. to 900 ° C., the range of choice of the other brazing material is widened in each step. In addition, the actual brazing temperature is equal to or higher than the solidus temperature,
Preferably, it is performed at a temperature several tens degrees higher than the liquidus temperature.

Further, since Pb, Zn, Cd and the like are not contained in the composition, the composition is suitable for a bonding process in a vacuum chamber.
The use of the flux (flux) required for the air treatment and the cleaning step are not required. Furthermore, since it has sufficient spreading properties and permeability, even when joining stainless steel or the like having a passivation film on the surface, Ni as a pretreatment is used.
There is no need for plating. It has excellent permeability and is suitable for joining members requiring airtightness and fine electronic components.

The other features and effects of the present invention will be described in the following detailed description based on specific examples and comparative examples.
It will be even clearer.

[0036]

BEST MODE FOR CARRYING OUT THE INVENTION (Preparation of Ag brazing material for test) An ingot of each composition having a diameter of 50 mm and a length of 400 mm is melted in a vacuum at about 1050 ° C., and then 350 to 75
Annealing at a temperature of 0 ° C. and rolling at a processing rate of 3 to 30% are repeated as many times as necessary to reduce the thickness to 0.3%.
mm, a plate-shaped brazing material having a predetermined width (for example, 30 mm) was obtained as a final finish by a slitter. this,
Test brazing materials shown in Tables 1 and 2 were used.

When a wire is required, the ingot is extruded to a diameter of 10 mm by an extruder, which is annealed (350 to 750 ° C.) and drawn (working rate: 3 to 30).
%) Can be repeated the required number of times to obtain a wire having a diameter of 0.1 mm.

[0038]

[Table 1]

[Table 2] (Evaluation method and evaluation conditions) As shown in FIG.
1. Prepare two unplated stainless steel plates 1 having a length of 125 mm and a thickness of 3 mm, and a part of both ends thereof as shown in FIG.
The test plate brazing material 2 having the composition shown in Table 1 was sandwiched between the overlapped portions by about 4 mm. The joining temperature is selected according to the liquidus temperature of the brazing material to be used (for example, 875 ° C. to 925 ° C.), and after brazing, the JI
The brazing property by S-Z-3192 (brazing joint shear test method) was evaluated. It should be noted that a stainless steel plate previously plated with Ni was similarly brazed and joined for reference.

With respect to the test brazing material of each composition, the shear strength (N / mm ² ), spreadability, and permeability were measured and observed, respectively, and comprehensive evaluation was performed based on the observation results. The results are shown in Tables 3 and 4. The evaluation of the shear strength was performed according to the following criteria.

[0040] · 350 N / mm ² or more when: Evaluation A (excellent) · 150~350N / mm ^2: Evaluation B (good) · 150 N / mm ² less than in the case: the evaluation of the evaluation C (bad) spread properties, Observe the flow (spread) of the brazing material on the surface of the SUS plate when the test brazing plate of each composition punched to a diameter of 15 mm is mounted on an unplated SUS plate and heated to 875-925 ° C. And evaluated according to the following criteria.

The brazing material area upon heating is 30 mm or more in diameter: Evaluation A
(Excellent)-Brazing material area during heating is 15 to 30 mm in diameter: Evaluation B (Good)-No spreading (or less than 15 mm in diameter): Evaluation C (Poor) The evaluation of permeability is shown in Fig. 1 (b). Then, at a point A of a gap of about 0.05 mm of the joining object 1 superposed on the two pieces, a brazing material of φ1.0 is set and melted, and the capillary on the opposite side is used by utilizing the capillary phenomenon of the molten metal. By observing the degree of arrival at the point B, the evaluation was made according to the following criteria.

Completely arrived at point B: evaluation A (excellent). Reached almost point B: evaluated B (good). Not arrived at point B: evaluated C (poor). Even if it satisfies all of the permeability, it does not satisfy the prerequisite that the brazing material of the present invention has a target temperature range, that is, a solidus temperature of 800 ° C. or more and a liquidus temperature of 900 or less, or a vacuum. Anything that caused contamination of the chamber was disqualified.

[0043]

[Table 3]

[Table 4]

[0044]

Examples and Comparative Examples Examples and comparative examples of Ag brazing materials having the compositions shown in Tables 1 and 2 will be specifically described below.

(Examples 1 to 4) The amount of Sn was set to 4.0%, and the amount of Mn was set to 0.1%, 0.3%, 2.5%, and 6.0%.
After performing a brazing treatment, the shear strength was measured. When the amount of Mn in the [Ag-Cu-Mn-Sn] alloy is 0.1%, 0.3%, 2.5%, or 5.0%, the shear strength is 150 to 350 N / mm ^2.
And exhibited good strength with evaluation B.

Further, according to an experiment on the spreadability when each brazing material punched to a diameter of 15 mm was placed on a SUS plate without Ni plating and brazing was performed, the Mn content was 0.1%.
In the case of 3%, 2.5%, and 5.0% (Examples 2 to 4),
It showed a spread of about 15 mm to 30 mm, and exhibited good spreadability as evaluated B. On the other hand, when the Mn content was 0.1% (Example 1), the spread area was less than 15 mm, and the evaluation was C.

In the permeability test, the Mn content was 0.1%.
%, 0.3%, 2.5%, and 5.0%, the brazing material penetrates the fine gap between the two stainless steel sheets that overlap each other, reaches the completely opposite side, and is evaluated. A and good joining condition were shown.

In the case where the Mn content is 0.1%, although the spreadability is slightly lacking, since it has a sufficient permeability, the bondability as a brazing material is good in actual use.
In particular, in the case of sealing a vacuum tube or joining fine electronic components, the permeability of the brazing material becomes a more important factor.
The brazing material is particularly suitable for applications requiring fine brazing or vacuum sealing.

The brazing materials of Examples 1 to 4 also have a solidus temperature (start of melting) of 800 ° C. or more and a liquidus temperature of 9 ° C.
00 degrees or less, and satisfies the target temperature range.

Although not shown in Tables 1 and 2, Examples 1 to
4 using an Ag brazing material having a composition of
When a plated SUS plate is selected, more stable shear strength (approximately 10 to 50% improvement) and good permeability are exhibited, and the spread area is almost the same in all of Examples 1 to 4 in terms of spreadability. It improved by 10 to 30%.

Comparative Example 1 As a comparative example, the Sn content was
[Ag-Cu-Mn] with 4.0% and Mn content of 7.5%
-Sn] to produce an ingot, and to form a plate having a thickness of 0.1 mm.
A brazing material was produced. This plate-shaped brazing material is
Sandwich between two unplated SUS plates and brazing
After performing, the shear strength was measured similarly. 150-35
0N / mm ^TwoIs obtained.
Demonstrated strength.

Next, Comparative Example 1 punched out to a diameter of 15 mm
According to the spreadability experiment in which a brazing material (Mn content: 7.5%) was placed on an unplated SUS plate and subjected to brazing treatment,
It shows a spreadability of 15 mm or more to about 30 mm (evaluation B), and both strength and spreadability are good. Furthermore, the permeability is good, and the bonding property as a whole is reasonable. However, an increase in the Mn content causes an increase in the amount of Mn having a high vapor pressure to evaporate, thereby causing a problem that the object to be joined and the inside of the furnace are contaminated. Further, depending on the brazing conditions, the Ag brazing material may spread too much, resulting in a lack of bonding stability. There has also been a problem that the quality of the brazing material during the production of the brazing material varies, and the stability of the quality is lacking.

From these examples and comparative examples, it can be seen that good bonding properties are exhibited when the Mn content is in the range of 0.1% to 6%.

(Examples 5 and 6) In Examples 1 to 4 and Comparative Example 1, the effect of adding Mn was shown.
Even if n and Ti in a predetermined amount coexist, the same effect is exhibited. In Examples 5 and 6, the Mn content was set to 1.5%, and T
i was 0.5% and 2.0%, respectively.
[Mn-Sn-Ti] ingot, and then 0.1 m thick
m plate-shaped brazing material was manufactured. These plate-shaped brazing materials were sandwiched between two unplated SUS plates as shown in FIG. 1, and after performing a brazing treatment, the shear strength was measured in the same manner.
If containing 0.5% Ti, it may indicate 350 N / mm ² or more Shear Strength (Evaluation A) and 150~350N / mm ² Shear strength (Evaluation B), 2.0 percent Ti
, A shear strength of 150 to 350 N / mm ² (evaluation B) was exhibited, and both exhibited good strength.

According to the spreadability experiment in which each brazing material punched to a diameter of 15 mm was placed on an unplated SUS plate and subjected to a brazing treatment at the same time, it was found that both brazing materials had a length of 15 m.
A spread of not less than m to about 30 mm (evaluation B) was exhibited, and good spreadability was exhibited. The results of observation of permeability using capillary action were also excellent.

For reference, the same Mn content of 1.5%
However, it has been found that when the Ti content is 5%, a huge CuTi compound is generated, the workability is reduced, and the step of processing into a plate or a line becomes complicated, which is not industrial.

(Examples 7 to 10 and Comparative Example 2) In Examples 1 to 6 and Comparative Example 1, [Ag-Cu-Mn-S
n] In the alloy, when the Mn content was 0.1% to 6.0%, or when a part of the Mn content was replaced with Ti, it was demonstrated that good bonding strength (shear strength) and spreadability were exhibited. In Examples 7 to 10, the shear strength and spreadability when Ni was further added to the alloy system of Examples 1 to 4 by 1.0% were evaluated. As a result, as shown in Table 3, the shear strength is improved by about 10 to 40% (evaluation AB), and the spreading property (wetting property) is further stabilized. The permeability was excellent regardless of the content of Mn or Ti.

On the other hand, when the Mn content is 7.5% as Comparative Example 2, as in Comparative Example 1, all of the shear strength after brazing, the spreading property, and the permeability have reached the acceptance criteria. However, it was confirmed that the evaporation amount of Mn increased and contamination in the furnace occurred, which was not preferable.

(Examples 11 to 12 and Comparative Examples 3 and 4)
In Examples 1 to 10 and Comparative Examples 1 and 2, [Ag-Cu
-Mn-Sn] The shear strength, spreadability, and permeability when the amount of Sn in the alloy was 4.0% were shown.
In Examples 11 and 12, the amount of Sn was 1.0%, respectively.
It was proved that a good joining effect was exhibited even when it was changed to 10%. That is, when the amount of Sn is 1.0% and 10%.
% Brazing material was manufactured, and these plate-shaped brazing materials were brazed between two unplated SUS plates as shown in FIG. After that, when the shear strength was measured,
When the amount of Sn is 1.0% and 10%, both are 150 to 35.
It exhibited a shear strength of 0 N / mm ² (evaluation B) and exhibited good strength. In addition, according to the spreadability experiment in which each brazing material punched to a diameter of 15 mm was placed on an unplated SUS plate and subjected to a brazing treatment at the same time, when the Sn amount was 1.0% (Example 9), Spreading of about 15 mm or more to about 30 mm (evaluation B) was exhibited, and good spreading properties were exhibited. S
When the amount of n was 10% (Example 10), the spread was 30 mm or more (evaluation A), and the spreadability was further improved. The permeability was the best irrespective of the change in the amount of Sn.

By adjusting the Sn content between 1.0% and 10%, the solidus temperature and the liquidus temperature can be set as targets while maintaining good bonding of the Ag brazing material. It becomes possible to control within the range of 800 ° C to 900 ° C.

On the other hand, when the amount of Sn was 0.1% in Comparative Example 3, the shear strength was 350 N / mm.
All the characteristics were good when ² or more (evaluation A) and the spread area was less than 15 to 30 mm (evaluation B). But,
The liquidus temperature of the Ag brazing material cannot be reduced to 900 ° C. or lower, and the first object of the present invention cannot be achieved. When the amount of Sn was set to 20% as Comparative Example 6, according to the expansibility test, it was 15 mm or more to 30 m or more.
m, and showed a spreadability of about m (evaluation B).
It was less than N / mm ² (evaluation C), indicating that the bonding strength was inferior. According to microscopic microscopic examination, the huge S
The cause is considered to be the formation of the n compound.

(Examples 13 and 14) In Examples 11 and 12 and Comparative Examples 3 and 4, the appropriate range of the amount of Sn was shown, but the same effect was obtained even when Sn and In within a predetermined amount coexisted. Can be In Examples 13 and 14, the amount of Sn was set to 4%, and the amount of In was set to 1.0% and 5.0%, respectively.
[Cu-Mn-Sn-In] ingot, and a plate-shaped brazing material having a thickness of 0.1 mm was manufactured. These plate-shaped brazing materials were sandwiched between two unplated SUS plates as shown in FIG. 1, and after performing a brazing treatment, the shear strength was measured in the same manner. In both Examples 13 and 14, 150 to 350 N
/ Mm ² (evaluation B), and exhibited good strength. Further, according to the spreadability experiment in which each brazing material punched to a diameter of 15 mm was placed on a SUS plate without plating and subjected to a brazing treatment at the same time, the spread of about 15 mm to 30 mm on the SUS plate without plating was shown ( Evaluation B) Good spreadability was exhibited.

Although not shown in the table, for reference, Sn
When the amount of In was increased to 10% while maintaining the amount of 4.0%, the workability was remarkably reduced, and the step of processing into a plate or a line became complicated, which was not industrial. .

(Examples 15 to 16 and Comparative Example 5) In Examples 7 to 10 and Comparative Example 2, [Ag-Cu-
[Mn-Sn-Ni] The preferred amount of Mn that affects the shear strength and spreadability when the amount of Ni in the alloy is 1.0% is shown. In Examples 15 and 16, the amount of Sn was set to 4.
The effect was confirmed by changing the amount of Ni to 0% and the amount of Mn to 1.5%. That is, each of the Ni contents is 0.1%
(Example 13) and 2.5% (Example 14) [A
g-Cu-Mn-Sn-Ni] ingot.
A plate-shaped brazing material having a thickness of 0.1 mm was manufactured. As shown in FIG. 1, these plate-shaped brazing materials are made of two sheets of unplated SUS.
After sandwiching between the plates and performing brazing treatment, the shear strength was measured in the same manner. In any of the examples, 150 to
It exhibited a shear strength of 350 N / mm ² (evaluation B) and exhibited good strength. In addition, when each brazing material punched to a diameter of 15 mm was placed on an unplated SUS plate and subjected to a brazing treatment at the same time to perform a spreadability experiment, both showed a spread of 30 mm or more on the unplated SUS plate ( Evaluation A), good spreadability was exhibited. The ingot was extruded to a diameter of 10 mm by an extruder, and this was annealed (350 to 750 ° C.) and drawn (working rate: 3 to 3).
0%) was repeated the required number of times to obtain a wire rod having a diameter of 0.1 mm, and the same shear strength was measured and the spreadability was evaluated. However, good characteristics were exhibited in the same Ni content range. did. The permeability was also the best.

On the other hand, as Comparative Example 5, the Ni content was 5.0%.
When the same brazing treatment was performed, the shear strength after joining was 150 to 350 N / mm ² (evaluation B).
According to the extensibility test, the brazing material punched to a diameter of 15 mm is 15 mm or more to 30 mm on a SUS plate without plating.
The degree of spread (evaluation B) was shown, and the permeability was also the best. However, the liquidus temperature rises and cannot be controlled to 900 ° C. or less, which is not preferable.

As described above, the amount of Ni in the brazing material is 2.5
%, The bonding strength (shear strength), spreadability,
It is possible to provide all the permeability and to control the liquidus temperature to 900 ° C. or less.

(Examples 17-18 and Comparative Examples 6-7)
In Examples 17 and 18, an appropriate amount of Cu in the [Ag-Cu-Mn-Sn] alloy or the [Ag-Cu-Mn-Sn-Ni] alloy is demonstrated. The amount of Cu contained in the Ag brazing material depends on the solidus temperature of the alloy together with the Ag content,
It is important to adjust the liquidus temperature within a predetermined value.

In Example 17, the Cu content was 2.5%
(Mn content 1.5%, Sn 4.0%), Ag content 9
2.0% (Ag + Cu = 94.5%, Ag / (Ag + C
u) = 97.4%). The shear strength after performing the brazing treatment is 150 to 350 N / mm ² (evaluation B),
It showed a spread of 15 mm or more to about 30 mm (evaluation B), and it was found that the brazing material completely penetrated to the opposite side in the gap between the objects to be joined, and all exhibited good characteristics. Further, the solidus temperature and liquidus temperature of the brazing material are set to 80
Control could be performed in the range of 0 to 900 ° C.

In Example 18, the Cu content was 10.0
%, The amount of Ag is 84.5% (Ag + Cu = 94.5%, A
g / (Ag + Cu) = 89.4%), the shear strength after brazing is 150 to 350.
N / mm ² (evaluation B). In the spreadability test,
A spread of 15 mm or more to about 30 mm (evaluation B) was shown, and the permeability was also the best, and it was found that all of the compositions exhibited good characteristics. Further, the solidus temperature and the liquidus temperature could be controlled in the range of 800 to 900 ° C.

On the other hand, in Comparative Example 6, the Cu content was 1.0% and the Ag content was 93.5% (Ag + Cu = 94.5).
%, Ag / (Ag + Cu) = 98.9%) was prepared. The shear strength after brazing is
150 to 350 N / mm ² (evaluation B), in the expansibility test, the brazing material punched to a diameter of 15 mm was not plated with SU.
Very good spreadability (evaluation A) of 30 mm or more was shown on the S plate, and both properties were good. In addition, it had excellent permeability. However, with this composition, the liquidus temperature could not be controlled to 900 ° C. or less.

Further, as Comparative Example 7, the amount of Cu was 20.
0%, the amount of Ag is 74.5% (Ag + Cu = 94.5%,
When Ag / (Ag + Cu) = 78.8%),
The shear strength after brazing is 150 to 35.
0N / mm ² (evaluation B), exhibiting good strength,
In the spreadability test, 15mm ~ on SUS plate without plating
A spread of 30 mm (evaluation B) was shown. The permeability was also the best. However, it has been difficult to control the solidus temperature to 800 ° C. or higher.

(Example 19 and Comparative Example 8)
In this example, the Cu content was set to 2.5% (Mn content was 0.5% and Sn was 1.0%), and the Ag content was increased to 96.0% (Ag
+ Cu = 98.5%, Ag / (Ag + Cu) = 97.5
%). With this composition, the shear strength after brazing treatment is 350 N / mm ² or more (evaluation A), and the spreadability is 1
Showing a spread of 5 mm or more to about 30 mm (evaluation B),
It had excellent permeability. Further, the solidus temperature and the liquidus temperature could be controlled in the range of 800 to 900 ° C.

On the other hand, in Comparative Example 8, the Cu content was 0.5% (Mn content was 0.5%, Sn was 1.0%), and Ag content was 0.5%.
98.0% (Ag + Cu = 98.5%, Ag / (A
g + Cu) = 99.5%). Shear strength after brazing is 350 N / mm ² or more (evaluation A)
And also excellent in permeability, but spreadability was 15 mm or less (evaluation C). Furthermore, the liquidus temperature is 900 ° C
Was found to be more unfavorable.

(Examples 20 to 23) In Examples 20 to 23, the Cu content of the Ag brazing material was set to 6.0%, and the Sn content was set to 1.0%, 4.0%, and 7.0%. , 10.0%, and the bondability when the remainder was Ag was measured. In these compositions, since Mn is not included, in the measurement of the spreadability, it is less than 15 mm, which is slightly inferior. However, the evaluation of the shear strength is B, the permeability is also the best, and the comprehensiveness indicating the bondability of the brazing material is shown. The evaluation was good. The target has a solidus temperature of 800 ° C. or higher and a liquidus temperature of 90 ° C.
0 ° C or less is satisfied. The Ag brazing material having these compositions is important when the permeability into the gap between two objects to be bonded is more important than the spreadability on a single plane. It is suitable when airtightness is required such as a vacuum tube.

Examples 24 to 26 In Examples 24 to 26, the Sn content was 4.0% and the Cu content was 6.0%.
, And the bondability was measured when the content of Ni was changed to 0.5%, 1.5%, and 2.5%, and the balance was Ag.
It can be seen that these compositions show good properties in all of the shear strength, spreadability, and permeability, and have excellent bondability.

(Examples 27 to 29) In Examples 27 to 29, it is demonstrated that the Ag brazing material of the present invention is applied not only to SUS but also to a wide range of members. That is, up to the twenty-sixth embodiment, an example in which only SUS (stainless steel) that is not plated is selected as an object to be joined is described.
No. 29, No plating S
US and alumina, unplated SUS and Cu, Cu and Cu
Was selected respectively. In each case, good shear strength, spreadability, and permeability were exhibited. Although not shown in the table, in place of unplated SUS, plated SU
In the case of S, more stable shear strength, spreadability, and permeability were exhibited.

Next, the Ag brazing material of the present invention and the existing Ag
Step brazing in which different joining portions are sequentially joined by combining with a brazing material will be described.

For example, as shown in FIG. 2, a Cu component 5 having a melting point of 1083 ° C. is bonded on a stainless steel substrate 3, and an arbitrary member 4 such as ceramics or alumina is bonded and covered on the Cu component 5. Consider the case. At this time, Cu
The component 5 cannot be joined to the lower stainless substrate 3 and the upper member 4 at the same time. If the joining is performed with the joining surface of the Cu component 5 facing upward, the brazing material will flow down and contaminate the Cu component 5 and further the lower stainless steel substrate 3.

Therefore, one surface is first joined, the Cu component 5 is turned in the opposite direction, and the other surface is joined so that the joining surface of the Cu component 5 always faces downward.

In the example shown in FIG. 2, the Ag brazing material 2 of the present invention is used for joining a stainless steel substrate 3 having a passivation film on its surface and a Cu component 5. The sliced Ag brazing material piece of the present invention is inserted between the stainless steel substrate 3 and the Cu component 5 arranged at a predetermined position, and is heated to an atmosphere of 920 ° C. to 925 ° C. to perform brazing. Since the working temperature is in this range, an adverse effect on the softening of the base material of the Cu component 5 can be avoided. In addition, since the Ag brazing material of the present invention has excellent spreadability, it is not necessary to perform Ni plating on the stainless steel substrate 3 prior to joining.

Next, using the existing Ag brazing material 7 having a melting temperature lower than the solidus temperature of the Ag brazing material of the present invention,
For example, an alumina substrate 4 is bonded to the other surface of the component 5. At this time, the assembly previously joined to the stainless steel substrate 3 is reversed so that the joining surface of the Cu component 5 faces downward. Then, the entire assembly is heated at a working temperature of 800 ° C. or less, and brazing is performed.

This series of brazing processes can be performed in the air or in a vacuum chamber.

Hereinafter, the effects of the step brazing using the Ag brazing material of the present invention will be demonstrated by Examples 30 to 33.

(Example 30) The first joint was joined in advance with the Ag brazing material of the present invention. Next, the second
Eutectic Ag brazing material [72% Ag-remainder Cu] (solidus temperature 780 ° C, liquidus temperature 780 ° C)
Was arranged, and a temperature at which the Ag brazing material of the present invention used for the first joint was not melted was selected and subjected to heat treatment together with the first joint. After the joining was completed, the first joint was evaluated for shear strength, permeability, and spreadability. As a result, the permeability A was evaluated, and the shear strength and spreadability were evaluated A and B.

(Example 31) The first joint was formed by using an existing brazing material JIS Z3265. BNi-2 (solidus temperature 9
95 ° C., liquidus temperature 1000 ° C.). Next, the second joint was joined with the Ag brazing material of the present invention. Further, a known eutectic Ag brazing material (solidus temperature 780 ° C, liquidus temperature 780 ° C) was arranged at the third joint. The temperature between the solidus temperature of the Ag brazing material of the present invention used for the second joint and the liquidus temperature of the eutectic Ag brazing material used for the third joint is the first temperature. Heat treatment was performed on both the joint and the second joint to complete the multi-step brazing. Thereafter, the second joint was evaluated for permeability, shear strength, and spreadability. The permeability is A,
Evaluations A and B were obtained for the shear strength and spreadability.

(Modification) In the embodiments 30 to 31, the non-plated stainless steel plates are mainly used as the objects to be joined.
Even when used for joining of Ni-plated stainless steel, good results were obtained in all of the shear strength, permeability, and spreadability. As shown in FIG. 2, even when one or both of the other metal or alloy such as Cu, or the non-metal such as alumina, good shear strength, permeability, and spreadability were obtained at the joint.

[0087]

According to the present invention, there is provided an Ag brazing material having a solidus temperature and a liquidus temperature of 800 ° C. to 900 ° C., which have not been present and whose existence has been desired. Become. In addition, since expensive Pd is not used, low-cost joining is possible.

When the Ag brazing material of the present invention is used as one of the brazing materials in the multi-step brazing, the selection range of the other brazing material and the selection of the joining operation temperature are greatly widened.

In Examples 27 to 29, it is demonstrated that the Ag brazing material of the present invention is applied not only to SUS but also to a wide range of members. That is, up to Example 26, an example in which only SUS (stainless steel) not plated was selected as an object to be joined, but in Examples 27 to 29, SUS without plating, alumina, and plating were used as objects to be joined. None SUS and Cu, Cu and Cu were selected. In each case, good shear strength, spreadability, and permeability were exhibited. Although not shown in the table, SU without plating was used.
When SUS with plating was used instead of S, more stable shear strength, spreadability, and permeability were exhibited.

In particular, it can be effectively used as one of the brazing materials in a multi-step brazing for joining components that are likely to be softened in the base material.

The present invention can be widely applied regardless of the material of the object to be joined, and good brazing can be performed without applying Ni plating to the surface of stainless steel or the like.

The present invention is suitable not only for atmospheric treatment but also for joining treatment in a vacuum chamber, and eliminates the need for a FLUX solvent treatment.

[Brief description of the drawings]

FIG. 1 is a diagram of a test piece for a shear strength and permeability test to demonstrate the effect of the present invention.

FIG. 2 is a view for explaining multi-step brazing using the Ag brazing material of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Joining member 2 Ag brazing material of the present invention 3 Stainless steel substrate 4 Alumina substrate 5 Cu part 7 Existing brazing material

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Isao Okutomi 1 Toshiba-cho, Fuchu-shi, Tokyo Inside Shibafu Engineering Co., Ltd. (72) Inventor Hiroshi Kaida 1-1-21 Komatsukita-cho, Nishinomiya-shi, Hyogo (72) Inventor Yoshikatsu Yamamoto 1-3-52 Komatsu Higashicho, Nishinomiya City, Hyogo Prefecture No. 1 Toshiba Corporation Fuchu Plant (72) Inventor Kiyoshi Nagano 1 Toshiba Town Fuchu City Tokyo Prefecture Toshiba Corporation Fuchu Plant

Claims (13)

[Claims] 1. 1.0% to 10.0% by weight of tin (Sn) and 2.5% to 10% by weight of copper (Cu)
And a balance of silver (Ag). 2. 1.0% to 10.0% by weight of tin (Sn) and 2.5% to 10% by weight of copper (Cu)
And a manganese (Mn) of 6.0% by weight or less and a balance of silver (Ag). 3. A method according to claim 1, wherein 1.0% to 10.0% by weight of tin (Sn) and 2.5% to 10% by weight of copper (Cu).
And 2.5% by weight or less of nickel (Ni) and the balance being silver (Ag). 4. The bonding A according to claim 2, further comprising 2.5% by weight or less of nickel (Ni).
g brazing material. 5. The Ag brazing material according to claim 2, wherein a part or all of the manganese (Mn) is replaced with titanium (Ti). 6. The Ag brazing material according to claim 1, wherein a part or all of said tin (Sn) is replaced with indium (In). 7. The Ag brazing material comprises silver (Ag) and copper (C).
The bonding Ag according to any one of claims 1 to 6, wherein a matrix mainly comprising u) is present surrounding a fine precipitation compound containing tin (Sn).
Brazing material. 8. The solidus temperature of the Ag brazing material is 800 ° C.
The joining brazing material according to any one of claims 1 to 6, wherein the liquidus temperature is 900 ° C or less. 9. 1.0% to 10.0% by weight of tin (Sn) and 2.5% to 10% by weight of copper (Cu)
And the balance is Ag, and its solidus temperature is 800 ° C.
Adjusting the first brazing Ag brazing material as described above; brazing a first part of an arbitrary member using the first brazing Ag brazing material; Brazing the second part of the member with a second joining brazing material having a liquidus temperature lower than the solidus temperature of the Ag brazing material. Attachment method. 10. 1.0% to 10.0% by weight of tin (Sn) and 2.5% to 10% by weight of copper (Cu)
And the balance is Ag, and its liquidus temperature is 900 ° C.
Adjusting the first joining Ag brazing material, and using the second joining brazing material having a solidus temperature higher than the liquidus temperature of the first joining Ag brazing material. Brazing a first portion of any member; and a second member of the member using the first joining Ag brazing material.
Brazing a portion; and a multi-step brazing method. 11. The multi-step brazing method according to claim 9, wherein the step of adjusting the first joining Ag brazing material further includes 6% or less of manganese (Mn). 12. The multi-step brazing apparatus according to claim 9, wherein the step of adjusting the first brazing filler metal further includes nickel (Ni) of 2.5% by weight or less. Attachment method. 13. The step of adjusting the first brazing Ag brazing material comprises: manganese (Mn) of 6% by weight or less;
The multi-step brazing method according to claim 9 or 10, further comprising nickel (Ni) of not more than weight%.