JPH02142698A - Complex solder - Google Patents

Abstract

PURPOSE:To improve the strength after joining by consisting the complex solder of solder which consists essentially of tin and lead, a metallic reinforcing material, and a flux which accelerates wetting of both, subjecting the solder, the reinforcing material and the flux to mixing and stirring, and melting the mixture by heating, thereby producing the composite solder. CONSTITUTION:Paste 2 consisting of powder solder 21 made of Sn-Pb and the flux 22 which accelerates wetting of the powder solder to metallic particles 3 and the metallic particles are mechanically mixed and stirred at room temp. The pasty material mixture in which the metallic particles are uniformly dispersed in the powder solder 21 and the flux is stuck to the surface of the metallic particles is produced. The pasty material mixture 4 is mounted between the joint surface 51 of a metal 5 and the joint surface 61 of a metal 6. The pasty material mixture is heated to melt the powder solder. The flux sticking to the metallic particles accelerates the formation of an alloy layer 25 consisting of the compd. (Ni-Sn or Cu-Sn) of the metallic particles and the molten solder 24. The solder and the reinforcing material are made into the composite material in this way, by which the strength after joining is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a composite solder in which metal particles and fibers are uniformly dispersed in the solder.

[Prior Art] Conventionally, tin-lead alloy (Sn-Pb)-based solder has a low melting point and can be easily heated and melted using a soldering iron or torch lamp. alloy,
It is used for joining nickel, lead, tin, f-lead, and their alloys. However, joining by soldering has a problem in that its strength is much lower than joining by brazing or welding.

For this reason, conventionally, for example, 5n-p with a changed composition ratio has been used.
b-based solder (graph in Figure 6), antimony (Sb)
Improvements in the tensile strength of button-pb solders such as 5n-Pb solder (graph in Figure 7) to which tertiary elements such as silver (＾g), bismuth (Bi), and copper (Cu) are added are possible. Various studies have been conducted.

[Problems to be Solved by the Invention] However, no significant improvement was observed in improving the strength of button-PB solder. In addition, some solders other than 5n-Pb have high tensile strength, but they are gold (A
It contains precious metals such as u), is expensive, or has a high melting point (S
There was a problem that it could not be handled as easily as n-Pb solder, and it could only be used for special joints.

Furthermore, there are methods that attempt to improve the tensile strength after bonding by adding reinforcing materials such as metal particles or metal fibers to the solder and mixing them to form a composite material.

However, simply adding reinforcing material to molten solder and mixing it will result in poor wetting of the reinforcing material with the molten solder due to the oxide film, adsorbed moisture, and adsorbed gas on the surface of the reinforcing material. There was a problem that it could not be uniformly dispersed.

The present invention aims to provide a composite solder that is inexpensive, has a low melting point, can be easily pumped, can disperse reinforcing materials almost uniformly in the solder, and can improve the strength after joining. .

[Means for Solving the Problems] The composite solder of the present invention includes a solder containing tin and lead as main components, a metal reinforcing material that increases the strength after joining, and a wetting of the reinforcing material by the solder. The solder, the reinforcing material, and the flux are mixed, stirred, heated, and melted to form a composite.

[Actions and Effects of the Invention] The composite solder of the present invention has the following actions and effects due to the above structure.

When powdered solder, reinforcing material, and flux are mixed and stirred, the reinforcing material is almost uniformly dispersed in the solder.

When these are heated and melted, the flux promotes wetting of the solder to the reinforcing material, so that the solder and the reinforcing material can be made into a composite material. Therefore, the strength after bonding can be improved. Also, by using inexpensive metals as reinforcing materials, inexpensive composite solders can be formed. Further, since the composite solder has a low melting point, it can be easily heated and melted using a soldering iron or a torch lamp.

[Example code] Examples of the composite solder of the present invention will be described based on the drawings.

1 and 2 show the manufacturing process of composite solder for manufacturing the present invention.

Reference numeral 1 indicates a composite solder used for joining metals together. This composite solder 1 is a composite obtained by mixing and stirring a solder paste 2 and metal particles 3 as a reinforcing material, and heating and melting the mixture.

The solder paste 2 is composed of a powdered solder 21 made of a tin-lead alloy and a liquid flux 22 that promotes wetting of the powdered solder 21 to the metal particles 3.

The flux 22 exists in a gap between a certain powdered solder 21 and the surrounding powdered solder 21. Furthermore, when the powdered solder 21 is heated and melted, the flux 22 is applied to the bonding surface 51 of the metal 5 and the bonding surface 6 of the metal 6 of the molten solder 24.
1 and also promotes wetting of the molten solder 24 to the metal particles 3.

The metal particles 3 are used to increase the tensile strength after metals are joined together, and also to increase the tensile strength of the molten solder 2 in the presence of the flux 22.
4 Nickel (Ni) particles, copper (Cu) with good wettability
particles or other metal particles or the like.

The manufacturing method of the composite solder 1 of this example is shown in FIGS. 1 and 2.
This will be explained based on the diagram.

As shown in Figure 1, at room temperature (e.g. 25°C), 5n-
A powdery solder 21 made of Pb, a solder paste 2 consisting of a flux 22 that promotes wetting of the powdered solder 21 to the metal particles 3, and a metal sinter 3 are mechanically mixed and stirred. The metal particles 3 are almost uniformly dispersed in the solder 21, and the flux 22 is distributed on the surface of the metal stringer 3.
A paste-like mixed material 4 to which is attached is manufactured (mixing step).

As shown in FIG. 2, the paste-like mixture 4 is installed between the bonding surface 51 of the gold α 5 and the bonding surface 61 of the metal 6. Then, the paste mixture 4 is heated to melt and stir the powdered solder 21. At this time, the flux 22 attached to the surface of the metal particles 3 becomes a compound of the metal particles 3 and the molten solder 24 (
An alloy layer 25 made of (Ni-3n or Cu-Sn)
promotes the formation of

When this is cooled, the metal particles 3 and the molten solder 24 are combined into a composite, and the composite solder 1 in which the metal particles 3 are almost uniformly dispersed in the solder 29 is manufactured, and the metal 5 and the gold H
6 will be reliably joined (1-combining step).

Figure 3 shows the particle volume ratio (vol) of the tensile strength (σB) of composite solder 1 in which nickel particles are added to molten solder 24
%) is a graph showing the amount of change.

As is clear from the graph in Figure 3, as the volume of nickel particles increases, the tensile strength improves, reaching a maximum of 9
．． A strength of 5 kgf/-, which could not be obtained with conventional 5n-Pb solder, was achieved.

In other words, the composite solder 1 made by dispersing the metal particles 3 almost uniformly in the molten solder 24 to form a composite of the molten solder 24 and the metal particles 3 dramatically increases the strength after bonding compared to conventional solder. Moreover, since this composite solder 1 is inexpensive and has a low melting point, it can be easily heated and melted using a soldering iron or a torch lamp, so that it can be easily soldered when joining metals.

4 and 5 show the manufacturing process of another composite solder 1 for manufacturing the present invention.

Here, 1 is a heating device for heating and melting the solder and flux 27. This heating device 7 includes a container 71 containing metal particles 3, solder and flux 27;
Metal particles 3, solder and flux 2 in the container 71
Electricity is supplied (O
N) or stop the supply of electricity to the electric smoker 12 (0
FF). Further, 8 is a rod member for mixing and stirring the metal particles 3, molten solder 26, and flux 27 in the container 71.

The manufacturing method of the composite solder 1 of this example is shown in FIGS. 4 and 5.
This will be explained based on the diagram.

Solder and flux 27 are placed in container 71.

Then, turn on the switch 13 and use the electric furnace 12 to
The solder and flux 27 are heated to a high temperature (e.g. 200~3
50℃) to melt.

At this time, in the container 71, the flux 21 is located at the liquid level of the molten solder 26 due to the difference in specific gravity. Next, when the metal particles 3 made of nickel particles or copper particles are placed in the container 71, the flux 27 is generated due to the specific gravity.
When passing through, it enters into the molten solder 26 with flux 27 attached to its surface. Therefore, an alloy layer 28 made of a compound (Hi-8n or CU-3n) of the metal particles 3 and the molten solder 26 is formed on the surface of the metal particles 3.
is generated.

In addition, the metal particles 3, molten solder 26, and flux 21 in the container 71 are mixed with the rod member 8 so as to be almost uniformly dispersed to form a composite, thereby making the composite solder 1.
WA-built.

Then, as shown in FIG. 5, the composite solder 1 in the container 71 is taken out and cooled, and then shaped into an arbitrary shape (for example, a plate shape).
A composite solder molded article 10 in which the metal particles 3 are almost uniformly dispersed in the solder 29 is manufactured. Further, this composite solder molded product 10 is supplied to a joint between metals (not shown) and heated and melted again using a soldering iron or a torch lamp, thereby joining the metals together.

[Other Examples] In this example, nickel particles, copper particles, or other metal particles that can be wetted by molten solder in the presence of flux were used as the metal reinforcement. Fibers may be used, or particles or fibers whose surface cannot be fused to molten solder in the presence of flux may be plated with nickel or copper.

[Brief explanation of the drawing]

Figures 1 and 2 are schematic diagrams showing the manufacturing process of composite solder for manufacturing the present invention, and Figure 3 shows particles of tensile strength of composite solder in which nickel particles are almost uniformly dispersed in molten solder. A graph showing the amount of change with respect to the volume fraction, Figures 4 and 5 are schematic diagrams showing the manufacturing process of other composite solders for manufacturing the present invention, and Figure 6 shows the composition ratio and tensile strength of the tin-lead alloy solder. A graph showing the relationship with strength, Figure 7 is 5n5
It is a graph showing the relationship between the amount of the third element added to 0-pb and the tensile strength. In the figure 1... Composite solder 2... Solder paste 3...
・Metal particles (reinforcing material) 21... Powdered solder 22...
・Flux 24.26...Melted solder 29...
・Solder 2... Solder base 1~3°, ・Metal particles (reinforcing material) 21... Powdered solder 22... Flux Figure 1 Particle body Figure 3 Area ratio (■01・mu) ＼ Figure 5 Figure 6 sn (wt ``le) Figure 7 Addition amount (wt・mu)

Claims (1)

[Scope of Claims] 1) Comprised of a solder containing tin and lead as main components, a metal reinforcing material that increases the strength after joining, and a flux that promotes wetting of the solder to the reinforcing material, A composite solder in which solder, the reinforcing material, and the flux are mixed and stirred and heated and melted to form a composite.