What is silver solders? Properties and Photos

In order to save money, many make silver solders with their own hands. We will clarify the features of the technology, the options for using the finished alloy.

If you are not confident in your abilities, it is better to get ready paste and not to waste time on questionable experiments.

What is an alloy

Pure silver is a soft metal, so it is not suitable for work. Most masters use mixtures, which include zinc, nickel, aluminum, copper, cadmium. Silver solder, except silver, includes zinc and copper. The seam, made with the help of such a composition, turns out to be strong and durable.

Compounds of silver, copper, zinc, have a high ability to melt. They are used for silver solder. To control its percentage composition, GOST 19746 74 has been developed. Solders, silver grades, are always indicated in the instructions for the products. The soldering seam, which is obtained in this way, is durable.

Solder of the grade PSrMc 37

Silver solder wire (PSrMz 37 and PSr-25) is used to connect surfaces made of brass. The form for its production is a solid sheet. It is cut into strips with a thickness of 1.5-2 mm. The gaps between the joined surfaces are filled with silver solder, capable of withstanding mechanical deformations and vibrations.

Chemical composition

The process technology is based on the use of silver solder intended for step soldering. Considering that the solder should withstand temperatures up to 600 ° C, its components are: 33% cadmium, 30% silver, 16% zinc, 20% copper. The composition is quite fragile, does not stand up to the vibrations. With an increase in the amount of silver to 52%, a fluid mixture is obtained, which can withstand multistage soldering.

Ancient recipe for cooking silver solder

Let's try to figure out how to make silver solder in the home. There are several options for its manufacture, each has its own nuances. To get the alloy, you need a coin (fifty kopecks) in 1924 , as well as five cents in 1962. For work you need: Ingus, silver, gas burner, spoon.

The production of silver solder begins with the melting of precious metal. Then add a five-kopeck coin. For complete mixing, the mixture is rolled on a spoon. The end result of mixing depends on the duration of this process. The disadvantage of this technology is the burnout of chemical components, which are necessary for soldering. Next, the master, who creates an alloy by his own hands, pours it into the Ingus, unrolls it without roasting. The resulting solder has 900 samples. When soldering, you need to prepare a fresh flux to ensure the quality of the work. The master monitors the flame in the gas burner to make the weld smooth and durable.

Engineering works

For technical works, silver solders containing up to 80 parts of silver, 16 copper, 4 zinc are used. Of interest are silver jewelery solders, whose composition: 2.8 parts of brass, 7 - silver, 0.2 - zinc. Before starting work, the brass is cleaned from the oxide film. To obtain 10 grams of such a solder, 999 silver is melted. Brass is added to the liquid metal, mixed in a spoon. After complete melting, the mixture is combined with zinc, the resulting composition is rolled. Next scissors cut the sheet rolled, weighed it on the scales. For effective work you need: a spoon, sandpaper, gas burner, scales, folds, a spoon for stirring. Silver solders can not be made without brass, silver, pure zinc, borax. Silver 96 or 96 samples are suitable for the production of technical solder. Such a metal can be obtained by burning silver products: galloons, gems, brocade.

Melting of solder

By melting the metals that make up the mixture, a silver solder for steel is produced in the crucible. Place the gel in the bugle by preparing special equipment: a drill, a container of water, a coal mixture, an iron hook, a crucible. First, it is necessary to melt the refractory, and then low-melting metals are added to the mixture. To make high-quality solder by hand, work needs to be divided into two stages. First, the crucible is removed from the furnace, the metal is connected in a container filled with water. As a result, fine-grained drops of solder appear. They are dried, then re-melted, covering with brown. Once the metal is completely melted, it is poured into special molds. After solidification bars or tiles rolled into thin strips. For later use, they are cut on a lathe with a thin wire.

Characteristics of medium melting compounds

What are home silver solders? Their properties are similar to those obtained in industrial conditions. The obtained solders have high strength, corrosion resistance, low melting point, high thermal conductivity. During operation, the composition fills the entire space between the surfaces to be soldered, gives an even and firm seam. If it is necessary to make a PSP-72 alloy, it is important to remember that when lithium is doped, the melting temperature with copper decreases. Such a composition is suitable for soldering steel parts that are resistant to chemical corrosion.

Solder Preparation at Home: Features and Algorithm

Soldering with silver solder at home assumes the reverse process - the transformation of the liquid metal into a solid state. First, silver is important to completely melt, then it is cast into the Ingus. All work is divided into three stages: making a spoon - smelters, adding flux, placing in a spoonful of charge, melt the source material, placing it in the Ingus.

Place a small cardboard rectangle on the bottom of the spoon, then a plate of a slightly larger size so that it wraps the edges of the spoon. Then thoroughly fry the sheets of cardboard. The bed must be concave in order to achieve the desired result. The process of melting solder at home is long, so you will have to be patient. Sorting charge is performed on a jewelry scales. The master will need the following materials:

• Jewelry electronic scales;
• 20 g of silver scrap of 916 samples;
• Silver scrap of 875 tests;
• Pure silver (12 grams);
• Borax;
• Metal for solder;
• gas-burner

All batch is divided into several heaps of 18-20 grams. Mix silver and scrap 875 samples. For one melting it will take about 6 grams of scrap and 42% of pure metal. Magnet it is purified of iron impurities.

To make solder, take silver of 875 tests and copper, the ratio should be 4 to 1 (you need a silver fifty kopecks and three copper coins). A flux of 1 to 10 is used for the flux. Next, the flame is adjusted. Do not use too much fire, this will lead to the combustion of metals, rather than melting them. A spoon is placed above the gas burner. In the process of melting, the color of silver changes, it flows down to the bottom.

Then put the Ingus near the flame to warm it. For high-quality melting, it is first smeared with wax. Do not allow the cooling and gloss of the melt, this will negatively affect the technical characteristics of the solder. The liquid metal is slowly poured into the heated Ingus. Then let the cold water run. After the bar is completely cooled, pull it out, turning the shape for this. Asbestos or cardboard coating can be used for 3-5 swimming trunks.

Repair of silverware

Beautiful chains, bracelets, earrings, forks, spoons, cup holders made of silver adorn the life of a person. But over time, precious metal products break down, in need of repair, restoration. To perform such work will require silver solder. For 925 tests you can make it yourself, using the advice of professional jewelers. For work, the following materials and tools will be needed: soldering tools of regular and irregular shape, casting for solder, scrap of silver. The simplest version of how to repair a broken chain is to take it to the jeweler. But if you want, you can cope with the problem and at home, saving money. To independently solder silver, it is necessary to master the algorithm of actions, technological methods, to study the physical characteristics of silver and its alloys.

Silver soldering rules

To perform such actions it is important to have information about the physico-chemical characteristics of the material. The melting point of silver is 960 degrees Celsius. From the point of view of jewelers, this is an average figure. For example, in copper, melting is possible at 1083 ° C, gold melts at 1063 ° C.

Depending on the components that make up the silver, their temperature will vary. In order to accurately know the characteristics of the alloy, you can use the technical reference books. The marking of silver solders implies a sequence of Russian letters and numbers. The figures characterize the percentage in the solder of a noble metal.

To repair the silver product, you need to prepare a soldering iron, to clean the surface of the product. Silver solder allows you to make strong, tight seams, resistant to corrosion. When repairing jewelry use solder containing more than 70 percent of silver, or a special pasta for soldering.

At home, alloys of silver, zinc, copper, cadmium are suitable for repairing small jewelry. The optimal composition for the "newcomers" will be the following composition: 45 parts of silver, 25 - copper, 30 - zinc. The melting of the components is carried out in a muffle furnace, a flux is required. The final mixture is poured onto a substrate, after cooling, passed through a rolling machine to obtain thin sheets. Their thickness should not exceed 0.5 mm. For household soldering, sheets with a width of 1-3 mm are needed. For home soldering of silver jewelry, it is undesirable to use compositions containing cadmium. This metal causes serious health problems. The place of soldering is exposed to air, oxides are formed. To prevent such a phenomenon, it is used in home rations of colophony (flux). When melting silver solder, it is important to monitor the uniform distribution of flux along the surface being treated. If there are doubts about your skills and theoretical knowledge of the soldering process, it is better to contact a professional jeweler.

It is not recommended to use at home cadmium-containing formulations, since during evaporation it negatively affects health. To prevent oxidation and other negative reactions, you can use flux (colophony). It is important that it is evenly distributed over the surface of the metal.

Conclusion

Soldering with silver will require the master of special skills and courage. The desired result is possible only if the flux, silver solder is correctly selected. For home repairs, silver scrap will not work, as the melting temperature will be lower than that of the restored product. Not suitable for work and compositions having equal to pure silver melting index. This will cause the solder flow during melting.