JP3316464B2 - Brazing paste - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brazing paste used for brazing same or different metals such as copper or copper alloy or SUS, and more particularly, to an organic binder and a solvent necessary for applying a brazing material to a brazing portion. And a brazing paste obtained by appropriately selecting a brazing paste.

[0002]

2. Description of the Related Art Brazing of copper and copper alloys is 5% by weight.
A copper alloy containing ７7% of P is inexpensive and can be brazed without using a flux, but has a high melting point of 800 to 900 ° C., which causes a problem that the base material is softened. That is, copper or copper alloy brazing, particularly heat-resistant copper alloys of the precipitation hardening type, solid solution type, and heat-resistant copper alloys of both types begin to soften at about 500 ° C. The characteristics deteriorate rapidly. For this reason, a phosphor copper brazing is used in which expensive silver is further added by 5 to 7% to lower the melting point. This brazing material also has a melting point of 7%.
It is relatively high at about 20 to 820 ° C. These are used in the form of a line, a bar or a plate.

[0003] Phosphorus copper brazing material having a melting point of 700 ° C or less is brittle, so that it becomes a powdery brazing material. An example of using this low melting point brazing material is disclosed in Japanese Patent Application Laid-Open No. 9-70686. The brazing material described therein has 6 to 15% by weight of Sn, 5 to 5%.
It has a composition containing 7% Ni and 5-8% P, with the balance being Cu, and has a low melting point of 620-650 ° C. A brazing filler metal having this composition is formed into a metal powder by an atomizing method, and a paste is formed by using polybutene, glycerin, liquid paraffin, mineral oil, or the like as a binder.

[0004] A brazing sheet is described in which this brazing material paste is applied to, for example, a plate-shaped core material made of copper or a copper alloy and heat-treated to form a brazing material on the surface of the core material. I have.

[0005] Further, as a brazing filler metal for brazing, a metal paste composition for brazing comprising metal powders such as copper and copper alloys and nickel alloys, a water-soluble polymer compound having a carboxyl group and water as essential components. Has been proposed (JP-A-56-154296).

[0006]

However, the brazing material paste disclosed in Japanese Patent Application Laid-Open No. 9-70686 uses polybutene, glycerin, liquid paraffin, mineral oil and the like as a binder, and H ₂ : 16%, N ₂ :
When the temperature is increased in an 84% atmosphere furnace, as shown in FIG. 6, they are completely thermally decomposed and volatilized to around 500 ° C., so that there is no carbide residue. In order to maintain a liquid state until volatilization, application to the flat plate surface is not particularly problematic, but if this paste is applied to a vertical surface and heated to the brazing temperature, it will flow down until the wax melts, There was a problem that it could not be brazed substantially.

On the other hand, in the brazing metal paste composition described in JP-A-56-154296, the melting temperature of the metal powder is as high as 750 to 1100 ° C., and
Since it has a temperature profile of water evaporation and binder thermal decomposition and volatilization as shown in FIG. 7, heating at 700 ° C. for several minutes in the above-mentioned atmosphere furnace results in significant residue of carbides.

The present invention has been made in view of the above-mentioned problems of the prior art, and aims to solve the following problems.

A first object of the present invention is to provide a conventional phosphor copper brazing or silver brazing which can be processed into a plate shape, a bar shape, a linear shape, etc. Heat-resistant copper alloy is softened. Therefore, it is an object of the present invention to provide a brazing paste that can be brazed at 700 ° C. or less.

A second object of the present invention is to generally use an expensive nickel alloy or silver solder for brazing stainless steel or iron, but use a low-tin, low-Ni, low-P alloy that cannot form a brittle compound. It is to provide a low melting point brazing paste.

A third object of the present invention is to provide a brazing paste free of residues such as carbides, in which the binder is thermally decomposed and volatilized when the heating temperature suitable for the paste of the low melting point brazing material is in the range of 500 to 700 ° C. It is to be.

A fourth object of the present invention is to apply a brazing paste to a vertical surface, leave the brazing material for a certain period of time, and heat the dried brazing material. The purpose of the present invention is to provide a brazing paste that does not flow down due to gravity.

A fifth object of the present invention is to provide an organic binder and an organic solvent which are simply mixed with a metal powder brazing material having a diameter of 10 to 200 μm by an atomizing method due to a difference in specific gravity between the organic material and the brazing material. The purpose is to provide a brazing paste that does not separate.

A sixth object of the present invention is to apply a brazing paste to one surface of a base material, and superimpose a bonding base material to be bonded on the brazing paste to confine the brazing material.
It is an object of the present invention to provide a brazing paste in which the brazing material is heated to several tens of degrees higher than the liquidus temperature of the brazing material in the range of 00 to 700 ° C. and rapidly cooled, so that carbides and voids are not involved in the brazing material.

A seventh object of the present invention is to provide a brazing paste which dries quickly so that it can be heated by a burner within several minutes after the application of the brazing paste to the joint of the base material. .

An eighth object of the present invention is to apply a brazing paste to one surface of a base material, and then superimpose a bonding base material to be bonded on the brazing paste on the base material. An object of the present invention is to provide a brazing paste that does not dry.

The present invention solves the above-mentioned problems, does not contain substances harmful to the human body during work or heating, and is inexpensive.
The purpose is to provide a brazing pace that can be stored for a long time.

[0018]

Means for Solving the Problems To solve the above problems, the first brazing paste of the present invention has a weight of 2%.
~ 11% P, 0.9-10% Ni and 4-26%
Weight average obtained by homopolymerization or copolymerization of 100 parts by weight of an alloy powder containing Sn, and the balance being Cu, and a compound in which one α-substituent of the α, α-substituted vinyl monomer is a methyl group. Molecular weight 10,000-20
It is characterized by mixing and dispersing 0.5 to 20 parts by weight of a high molecular weight polymer having a molecular weight of 000 and 5 to 20 parts by weight of an organic solvent having a boiling point of 250 ° C. or lower and containing no aromatic group. It is assumed that.

Since the brazing filler metal having the above composition, which has been formed into a metal powder by the atomizing method, has a low melting point of 600 to 650 ° C., in joining copper and a copper alloy, copper oxide is joined without flux by a reducing action of phosphorus. can do. In particular, it has a feature that it can be brazed at a temperature lower than the softening temperature of the base material in joining a heat-resistant copper alloy.

The first brazing paste having the above structure has a relatively quick drying property in which the solvent evaporates and dries at room temperature for several minutes after application, so that automatic brazing by heating with a gas burner is also possible. Depending on the size and structure of the workpiece, a brazing paste suitable for drying conditions at room temperature for several minutes to several tens of minutes after coating can be prepared as a brazing type in a furnace. Even when the film is applied to a vertical surface, dried, and heated, it does not flow down until the brazing material is melted. Further, as shown in FIG. 4, the binder is completely thermally decomposed and volatilized up to around 500 ° C., so that a strong joint free from voids and carbide residues can be obtained.

The second brazing paste of the present invention is characterized in that glycerin tri-12-hydroxystearate is added in an amount of 0.5 to 5 parts by weight to 100 parts by weight of the first brazing paste. Is what you do.

While the first brazing paste has a relatively quick drying property, by adding the above additives,
After application, a predetermined viscosity can be maintained at room temperature for several hours. Therefore, not only a film with a uniform thickness by printing, but also a non-uniform application using an applicator or a spatula-shaped coating jig, if the base material to be bonded is overlapped after being applied to the base material, , And a strong junction can be obtained. Furthermore, long-term storage stability of the paste is ensured. Further, since the solvent and the binder have a temperature profile of evaporation, thermal decomposition, and volatilization as shown in FIG. 5, it is possible to obtain a joint free from voids and carbide residues.

The third brazing paste of the present invention is an alloy comprising 0.3 to 3% by weight of P, 2 to 4.5% of Ni and 4 to 20% of Cu, with the balance being Sn. The weight average molecular weight obtained by homopolymerization or copolymerization of 100 parts by weight of the powder and a compound in which one α substituent of the α, α-2-substituted vinyl monomer is a methyl group is 10,
000-200,000 high molecular weight polymer to 0.5-
20 parts by weight and 5 to 20 parts by weight of an organic solvent having a boiling point of 250 ° C. or less and containing no aromatic group are mixed and dispersed.

The brazing filler metal having the above composition, which is made into a metal powder by the atomizing method, has a low melting point of 450 to 600 ° C. The brazing paste having the above-mentioned structure can be used in a vacuum or reducing atmosphere furnace without producing brittle compounds such as NiP, SnP, and FeP between copper or copper alloys and the same or different metals such as stainless steel and iron. Strong brazing without carbide residue.

Further, the fourth brazing paste of the present invention is characterized in that glycerin tri-12-hydroxystearate is added in an amount of 0.5 to 5 parts by weight to 100 parts by weight of the third brazing paste. Is what you do.

While the third brazing paste is quick-drying, by adding the above additives, it can be used for a long time.
It is the same as the second brazing paste that the predetermined viscosity is maintained and the long-term storage stability of the paste is ensured.

As a binder which does not generate carbides during brazing, as a result of intensive studies, it can be obtained by homopolymerization or copolymerization of a compound in which one α-substituent of the α, α-substituted vinyl monomer is a methyl group. It has been found that a high molecular weight polymer having a weight average molecular weight of 10,000 to 200,000 is effective.

That is, an α-1-substituted vinyl monomer,
A high molecular weight polymer obtained by using a compound in which one of the α-substituents of the α, α-substituted vinyl monomer is other than a methyl group generates a carbide at the time of brazing, and is not used in the present invention.

Further, the formation of carbides at the time of brazing has been confirmed in all other condensation-type high molecular compounds such as polyester resins, melamine resins, urea resins, and phenol resins, and cannot be used.

One of the α, α-2-substituted vinyl monomers, α
As the compound in which the substituent is a methyl group, methyl methacrylate, ethyl methacrylate, propyl methacrylate,
Normal butyl methacrylate, isobutyl methacrylate, tertiary butyl methacrylate, methacrylic acid 2
-Ethylhexyl, normal octyl methacrylate, isooctyl methacrylate, isodecyl methacrylate, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl methacrylate, isobutylene methacrylate and the like.

The high molecular weight polymer in the present invention comprises the above α,
It can be obtained by subjecting a compound in which one α substituent of the α-2-substituted vinyl monomer is a methyl group to radical polymerization or ionic polymerization by a known polymerization method such as bulk polymerization, solution polymerization or suspension polymerization.

The weight average molecular weight of the obtained polymer is 10,
If it is less than 000, the ability to hold the brazing material on the base material is reduced, and it cannot be used. On the other hand, for a polymer having a weight average molecular weight of more than 200,000,
At the time of brazing, a considerable amount of carbide tends to be formed.
Therefore, the weight average molecular weight of the polymer is 10,000 to 20
It is preferably set to 0000.

The term "weight average molecular weight" as used herein refers to a value determined by gel permeation chromatography in terms of a polystyrene standard sample.

The mixing ratio between the high molecular weight polymer and the brazing material is as follows:
0.5 to 20 polymer based on 100 parts by weight of brazing material
Must be parts by weight. If the content of the high molecular weight polymer is less than 0.5 parts by weight, the ability as a binder is not exhibited, and the brazing filler material is dropped. If the content exceeds 20 parts by weight, it is likely that the decomposition and volatilization gas of the high molecular weight polymer is not efficiently exhausted from the furnace during brazing, which is not preferable in terms of safety and health. Therefore, the content of the binder should be 0.5 to 20 parts by weight.

The organic solvent to be used in forming the paste may be any compound that volatilizes before the brazing material, and examples thereof include compounds having a boiling point of 250 ° C. or less.
However, in the case where the brazing conditions and the like change, even in an organic solvent having a boiling point of 250 ° C. or less,
It has been clarified that some organic solvents are contained in the brazing material and the binder during brazing, which adversely affects the brazing.

By examining various cases, it has been clarified that when an aromatic compound is used as an organic solvent for pasting, carbides are easily generated during brazing.

In the present invention, the organic solvent for forming a paste is a non-aromatic compound having a boiling point of 250 ° C.
The following compounds may be used, but an aliphatic hydrocarbon mixture having an initial boiling point of 100 ° C. or higher and a dry point of 250 ° C. or lower is more preferable.

Further, considering the applicability of the paste,
A single compound other than aliphatic hydrocarbons, having a boiling point of 150 to
Compounds in the range of 250 ° C. can be used in combination.
By using these single compounds together, the leveling property to the base material is also improved.

The mixing ratio of the organic solvent when forming the paste is as follows:
In consideration of the viscosity of the paste, 5 to 50 parts by weight is appropriate for 100 parts by weight of the brazing material.

When the organic binder and the organic solvent are simply mixed with the brazing filler metal, the difference in specific gravity between the organic substance and the brazing filler metal is large. Sometimes the paste can no longer be used. In order to avoid this phenomenon, it is effective to add wax in the paste in advance. However, the wax may form carbides at the time of brazing, which may adversely affect the brazing.

As a result of intensive studies, the inclusion of glycerin tri-12-hydroxystearate, a kind of wax, in the paste ensures long-term storage stability of the paste and does not adversely affect brazing. It became clear.

However, due to heating during brazing,
Since glycerin tri-12-hydroxystearate softens and causes a phenomenon in which the brazing filler metal flows, the addition amount must be 5 parts by weight or less based on 100 parts by weight of the paste.

[0043]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Example 1 An alloy containing 4% by weight of P, 4.5% of Ni and 16.5% of Sn and the balance of Cu was obtained by gas atomization to obtain an average particle size of 40%.
An alloy powder of 100 μm in μm and Max was produced. The thermal properties of this alloy have a semi-melting range of 594-618 ° C.

100 parts by weight of the above alloy powder, 2 parts by weight of polyisobutylene having a weight average molecular weight of 110,000 as a binder, and an initial boiling point of 159 ° C. as an organic solvent.
A brazing paste was prepared by mixing and dispersing 10 parts by weight of an aliphatic hydrocarbon having a dry point of 193 ° C. This corresponds to the brazing paste of claim 1.

This brazing paste was
A test piece for a drop test was applied on a 30 × 30 × 0.8 t copper alloy plate, and was heated at 680 ° C. for 5 minutes and 700 ° C. using a continuous furnace of 15% H ₂ and 85% N ₂ atmosphere.
As a result of heating for 5 minutes, the former was quadrupled and the latter was 5.4 times.
Good results were obtained with a double spread and no residue on the surface.

Further, as shown in FIG.
The brazing paste was applied to the entire surface of a copper alloy plate of 0 × 70 × 0.8 t with a thickness of 1 mm, and a bonding test was performed in which copper alloy plates having the same area were overlapped. The heat treatment conditions are as follows: after evacuation, in a 15% H ₂ , 85% N ₂ atmosphere, 670
As a result of heating at 10 ° C. for 10 minutes and then quenching, no void was observed over a longitudinal section of the joint of 100 mm. FIG. 1B is a diagram (a diagram based on a micrograph) showing the joint structure.

At the joint boundary with the base material Cu, a strong alloy bond in which primary Sn crystals are diffused is formed. In the brazing material, there are no carbides or voids, and compounds such as CuP and NiP are tough. The eutectic structure is shown.

Example 2 The same alloy powder as in Example 1 is used. 100 parts by weight of this alloy powder and, as a binder, a polymer of methyl methacrylate and normal butyl methacrylate having a weight average molecular weight of 100,000
Parts by weight and, as an organic solvent, an initial boiling point of 159 ° C. and a dry point of 19
5 parts by weight of an aliphatic hydrocarbon at 3 ° C., 7 parts by weight of 1-methyl 2-pyrrolidone, 3 parts by weight of butyl carbitol acetate, and glycerin = tri-1
2 parts by weight of 2-hydroxystearate was mixed and dispersed to prepare a brazing paste. This corresponds to the brazing paste of claim 2.

This brazing paste was used for
A test piece for a drop test was applied on a 30 × 30 × 0.8 t copper alloy plate, and was heated at 680 ° C. for 5 minutes and 700 ° C. using a continuous furnace of 15% H ₂ and 85% N ₂ atmosphere.
Heating the results of the 5 minutes, 3 times in the former and the latter at the indicated four times the spread, either on the surface of some Sn ₂ P, Ni ₃
Although a residue of a compound such as P was generated, the amount of the residue at a heating temperature of 700 ° C. was small.

Further, as shown in FIG.
The brazing paste was applied to the entire surface of a copper alloy plate of 0 × 70 × 0.8 to a thickness of 1 mm, and a copper alloy plate having the same area was overlapped to perform a bonding test. The heat treatment conditions are as follows: after evacuation, in a 15% H ₂ , 85% N ₂ atmosphere, 670
As a result of heating at 10 ° C. for 10 minutes and then quenching, voids could not be visually observed in the longitudinal section of the joint at 100 mm, but the structure of the joint shown in FIG. In the figure based on this, small voids were observed on the joint line and in the brazing alloy layer. For this reason, in the overlapped portion, although there is a slight decrease in the bonding strength and the sealing property, it can be sufficiently used for seepage and diffusion bonding utilizing capillary force.

Comparative Example 5% P by weight, 4.5% N by weight
100 parts by weight of an alloy powder prepared by gas atomizing an alloy containing i and 15% of Sn and the balance being Cu, 15 parts by weight of an acrylic resin of a polymer compound having a carboxyl group, and 5 parts by weight of water Were mixed and dispersed to prepare a brazing paste. This is a brazing paste for Ni brazing. A cereal-drop test using this brazing paste was performed (FIG. 3).
(A)).

The above alloy powder has an average particle size of 45 μm and M
ax is 150 μm. The thermal analysis characteristic has a transformation point at 495 ° C., a solid phase temperature of 585 ° C. and a liquid phase temperature of 625 ° C.

As a result of heating at 700 ° C. for 10 minutes by using a continuous furnace in an atmosphere of 15% H ₂ and 85% N ₂ , the spread of the brazing material was good, but the black was left on the initial coating portion. Residue was observed. Further, as shown in FIG. 3B, many voids including carbides were generated in the cross-sectional structure.

The cross section from which the superposed test pieces were peeled off had a porous shape and the bonding strength was degraded.

The cecil drop test here is a test piece (30 mm × 30 m) of a clean copper alloy.
This test refers to a test in which a brazing paste applied to a size of 15 mmφ × 0.8 mm is heated on m × 0.8 mmt) to examine its wetting and spreading.

Example 3 An alloy containing 0.3% of P, 2% of Ni and 4% of Cu and the balance of Sn was prepared by a gas atomizing method to have an average particle size of 45 μm.
An alloy powder having a Max of 106 μm was prepared. The thermal properties of this alloy have a semi-melting range of 225-470 ° C.

100 parts by weight of the above alloy powder, 2 parts by weight of polyisobutylene having a weight average molecular weight of 110,000 as a binder, and an initial boiling point of 159 ° C. as an organic solvent.
A brazing paste was prepared by mixing and dispersing 10 parts by weight of an aliphatic hydrocarbon having a dry point of 193 ° C. This corresponds to the brazing paste of claim 3.

This brazing paste was mixed with 100 × 7
A 1 mm thick copper alloy plate was applied over the entire surface to a 0 × 0.8 t copper alloy plate, and a bonding test was performed in which copper alloy plates having the same area were overlapped. The heat treatment was carried out in a vacuum at 500 ° C. for 10 minutes, followed by rapid cooling.
No voids were observed over mm.

The primary crystal of Sn formed an alloy on the surface of the base material at the junction with the base material Cu. In addition, the brazing material portion did not have carbides or voids and showed alloy joining.

Example 4 The same brazing paste as in Example 3 was applied to the entire surface of a SUS304 plate of 100 × 70 × 1 t with a thickness of 1 mm, and SUS304 having the same area was coated.
A joining test in which the plates were overlapped was performed. The heat treatment was performed in vacuum at 700 ° C. for 10 minutes, followed by rapid cooling. As a result, no voids were observed over a 100 mm longitudinal section of the joint.

The boundary between the base material and the base metal is
The interface where the layer appeared and was free of compounds such as NiP.

Example 5 An alloy containing 0.3% by weight of P, 2% of Ni, and 4% of Cu and the balance of Sn was prepared by gas atomization to have an average particle diameter of 45 μm.
An alloy powder having a Max of 106 μm was prepared. The thermal properties of this alloy have a semi-melting range of 225-470 ° C.

100 parts by weight of the above alloy powder, 7 parts by weight of a polymer of methyl methacrylate and normal butyl methacrylate having a weight average molecular weight of 100,000 as a binder and an organic solvent having an initial boiling point of 159 ° C. Dry point 1
5 parts by weight of an aliphatic hydrocarbon at 93 ° C., 7 parts by weight of 1-methyl 2-pyrrolidone, 3 parts by weight of butyl carbitol acetate, and 2 parts by weight of glycerin tri-12-hydroxystearate as additives. Were mixed and dispersed to prepare a brazing paste. This corresponds to the brazing paste of claim 4.

This brazing paste was used for
A test piece for a drop test was applied on a 30 × 30 × 0.8 t copper alloy plate, and heated at 600 ° C. for 5 minutes using a continuous furnace in an atmosphere of 15% H ₂ and 85% N _2. As a result, the spread was as good as 5 times. Further, although some compound residues appear on the surface, it is effective for bonding utilizing capillary force, and when a relatively high heating temperature of 600 ° C. is employed, S having high bonding strength is formed on the surface of the bonding base material.
Several tens of μm of the n alloy layer was formed.

In addition, a brazing paste was prepared for Example 6 and Comparative Example 2, and Examples 1 to 5
Along with Comparative Example 1, the composition, physical properties and overall evaluation are described in (Table 1) to (Table 3).

[0067]

[Table 1]

[0068]

[Table 2]

[0069]

[Table 3]

The methods for evaluating physical properties are as follows.

Drying property: 100 μm at 10 mm × 50 mm
Printed to a thickness of m and measured for surface tack after standing at room temperature for 10 minutes. ◎; no tack. ○; slight tack. △: tacky. ×: tacky with falling off. Stability: Observation of the condition after leaving the brazing paste at room temperature for one week. ○: No separation or thickening, stable ×: Different from the initial condition Brazing material retention: 10 mm × 50 mm, 100 μm thick Print and apply, 200 ° C with the application surface held vertically
× Measure the sagging distance of the brazing material when held for 5 minutes ○: No sagging △: Sagging less than 5 cm ×: 5 cm
With the above-mentioned sagging Spreadability of brazing material: Observation of spread by cecil drop test ○: Spread more than 3 times ×: Spread of less than 3 times Presence or absence of residue after brazing; Observation of black residue after brazing.

[0072]

As described above, the brazing paste according to the present invention has the following effects.

(1) Since brazing can be performed at a temperature of 700 ° C. or less, brazing having high mechanical strength can be obtained without softening copper or a copper alloy as a base material.

(2) Since the binder and the solvent are appropriately selected, they are completely thermally decomposed and volatilized before the brazing material is melted. Therefore, even with brazing in which the brazing material is confined, a strong joint free of voids and carbide residues can be obtained.

(3) The brazing paste having a relatively quick drying property can be automatically brazed by heating with a gas burner or the like in a short time after application.

(4) Since the drying property can be adjusted by adding an additive, various coating methods can be applied in addition to printing. Further, the paste can be stored for a long time.

(5) Even if the brazing material is heated after being coated on a vertical surface and dried, it does not flow down until the brazing material is melted.

(6) In addition to copper or copper alloy, strong brazing can be performed between the same or different metals such as stainless steel and iron without generating brittle compounds.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a brazed joint in Embodiment 1 of the present invention and an enlarged view of the joint structure.

FIG. 2 is an enlarged view of a cross section of a brazed joint in Embodiment 2 of the present invention and a structure of the joint.

FIG. 3 is an enlarged view of a cereal-drop test and a joint structure thereof in a reference example.

FIG. 4 is a diagram showing a temperature profile of evaporation, thermal decomposition, and volatilization of a solvent and a binder constituting the brazing paste of the present invention.

FIG. 5 is a diagram showing a temperature profile of evaporation, thermal decomposition, and volatilization of a solvent and a binder constituting another brazing paste of the present invention.

FIG. 6 is a diagram showing a thermal decomposition and volatilization temperature profile of a binder constituting a brazing paste in a conventional example described in JP-A-9-70686.

FIG. 7 is a diagram showing a temperature profile of evaporation, thermal decomposition, and volatilization of water and a binder constituting a brazing paste in a conventional example described in JP-A-56-154296.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-9-70686 (JP, A) JP-A-4-238693 (JP, A) JP-A-2-268995 (JP, A) JP-A-8-86 1373 (JP, A) JP-A-5-185285 (JP, A) JP-A-10-144718 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23K 35/363 B23K 35 /twenty two

Claims (4)

(57) [Claims] 1. P, weighing 2 to 11%, 0.9 to 10%
Of Ni and 4 to 26% of Sn, the balance being 100 parts by weight of an alloy powder composed of Cu, and homopolymerization or copolymerization of methacrylates.
Weight average molecular weight obtained from 10,000 to 200,
A polymer having a weight average molecular weight of 10,000 to 200,000 obtained by homopolymerization or copolymerization of isobutylene and a polymer having a boiling point of 0.5 to 20 parts by weight; Aliphatic system at 250 ° C or lower and containing no aromatic group
A brazing paste characterized by mixing and dispersing 5 to 20 parts by weight of an organic solvent comprising a hydrocarbon mixture . 2. The brazing paste 1 according to claim 1.
00 parts by weight, glycerin = brazing paste characterized by comprising tri 12-hydroxy stearate was added 0.5 to 5 parts by weight. 3. P, 2-4.5% by weight of 0.3-3%.
Of Ni and 4 to 20% of Cu, with the balance being 100 parts by weight of an alloy powder composed of Sn, and homopolymerization or copolymerization of methacrylates.
Weight average molecular weight obtained from 10,000 to 200,
A polymer having a weight average molecular weight of 10,000 to 200,000 obtained by homopolymerization or copolymerization of isobutylene and a polymer having a boiling point of 0.5 to 20 parts by weight; Aliphatic system at 250 ° C or lower and containing no aromatic group
A brazing paste characterized by mixing and dispersing 5 to 20 parts by weight of an organic solvent comprising a hydrocarbon mixture . 4. Brazing paste 1 according to claim 3.
A brazing paste characterized by adding 0.5 to 5 parts by weight of glycerin tri-12-hydroxystearate to 00 parts by weight.