RU2367552C1 - Solder alloy on basis of silver - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: solder alloy can be used in jewellery industry, electronics, electrotechnics and instrument engineering. Solder alloy contains components in a following ratio, wt %: silver 39-41; copper 30-35; zinc 22-26; indium 1-3; tin 1-2. Alloy of solder alloy allows wide range of strength limit 390-530 MPa. Introduction of tin provides receiving of solder alloy in the form of powder with wide range of size composition 50-315 micrometre. Combinations of indium and tin are almost harmless for man body.

EFFECT: decreasing of problems at manufacturing and usage of solder alloy at manufacturing and expansion of manufacturing capabilities of application of particular solder alloy.

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Description

The present invention relates to the field of metallurgy of silver-based alloys and can be used in the jewelry industry, electronics, electrical engineering and instrumentation.

Known solders based on silver, copper and zinc, designed for soldering in the temperature range of 610-1000 ° C and widely used to obtain integral products (Lashko N.F. Soldering of metals. / N.F. Lashko, S.V. Lashko. - M .: "Engineering", 1967, p.211).

Known solder based on silver grade PSR 45 (GOST 19738-74), containing, wt.%:

Silver 44.5-45.5 Copper 29.5-30.5 Zinc 23.5-26.0

This solder has an increased soldering temperature of 780 ° C, high strength σ _B = 363-500 MPa, but low ductility δ = 10-15%, which limits its use.

The closest in the set of essential features, in terms of technical nature and the achieved result, is a solder based on silver grade PSR 40 (GOST 19738-74), containing, wt.%:

Silver 39.0-41.0 Copper 16.4-17.4 Zinc 16.6-17.8 Cadmium 26.0-26.5

This solder has a reduced soldering temperature of 620 ° C, satisfactory strength σ _B = 372-431 MPa and a sufficiently high ductility δ = 25-30%. However, a significant drawback of this solder is its cadmium content. Cadmium compounds are very toxic, have harmful effects on the human body and cause occupational diseases, which creates certain difficulties in the manufacture and use of this solder in production, imposes increased requirements for industrial safety and ultimately reduces the technological possibilities of using this solder.

The main objective of the invention is to expand the technological capabilities of the use of solder and increase industrial safety.

The problem is achieved in that the silver-based solder containing copper and zinc additionally contains indium and tin in the following ratio of components, wt.%:

Silver 39-41 Copper 30-35 Zinc 22-26 Indium 1-3 Tin 1-2

The inventive solder in comparison with the prototype is characterized by distinctive features that allow you to expand the technological capabilities of the use of solder and increase production safety.

In relation to the prototype, the proposed solder has the following distinctive features: silver based solder containing copper, zinc, additionally contains indium, tin in the following ratio, wt.%:

Silver 39-41 Copper 30-35 Zinc 22-26 Indium 1-3 Tin 1-2

Compounds of indium and tin are practically harmless to the human body, which significantly reduces the difficulties in the manufacture and use of this solder in production, does not impose increased requirements for industrial safety. In addition, the proposed alloy has an extended interval of tensile strength of 390-530 MPa, which allows it to be used for soldering a wider range of alloys. One of the main conditions for the reliability of the weld when soldering is the identity of the mechanical properties of the weld and the parts to be welded (Strizhko L.S. Metallurgy of gold and silver. / L.S. Strizhko. - M .: MISIS, 2001, p.336). Changing the content of components in the proposed alloy, it is possible to select technological characteristics that satisfy the optimal soldering conditions. Thereby expanding the technological possibilities of using this solder, including for the manufacture of consumer goods.

Thus, there is a causal relationship between the hallmarks and the task at hand. Replacing cadmium with indium in a silver-based solder containing copper and zinc allows us to expand the technological capabilities of using solder and increase production safety.

To obtain the proposed solder, compositions were prepared whose chemical composition and properties, in comparison with the known solder, are given in Tables 1 and 2.

Table 1 Solder Composition No. The content of components, wt.% Silver Copper Zinc Cadmium Indium Tin Proposed one 39.0 30,0 26.0 - 3.0 2.0 2 40,0 32,5 24.0 - 2.0 1,5 3 41.0 35.0 22.0 - 1,0 1,0 Famous four 40,0 16.9 16.9 26.2 - -

table 2 Solder Composition No. Temperature ° C Strength, σ _V , MPa Elongation, δ,% solidus liquidus soldering Proposed one 600 635 635 380-450 20-24 2 618 650 650 380-440 22-26 3 640 670 670 370-430 24-30 Famous four 595 620 620 372-431 25-30

The addition of tin to the solder in the proposed range of components provides the proposed solder in the form of a powder by mechanical grinding in a wide range of particle size distribution of 50-315 microns. It should be noted that the proposed solder in the form of a powder is one of the most effective materials used for high-quality soldering of electrical contacts.

Thus, the use of the inventive solder in comparison with the prototype allows you to expand the technological capabilities of the use of solder and increase production safety.

Claims (1)

Silver-based solder containing copper and zinc, characterized in that it additionally contains indium and tin in the following ratio, wt.%:
Silver 39-41 Copper 30-35 Zinc 22-26 Indium 1-3 Tin 1-2