What is the melting temperature of solder

Brands of soft solders and fluxes for soldering with a soldering iron

For soldering with a soldering iron, solder is used, and in order for the solder to spread well over the surface of the parts being connected by soldering, a substance called flux is used. Depending on the metal of the parts and their size, the strength and tightness of the soldering, it is necessary to choose a specific brand of solder and flux. The information in the tables will help you select the required solder and flux for soldering.

Brands of soft solders for soldering with a soldering iron

The main component when soldering with an electric soldering iron is tin-lead solder. It is available in the form of wire or tube of different diameters. The tubular solder inside is filled with rosin. This type of solder is very convenient when working, since it does not require additional flux to the soldering iron tip.

Solder is an alloy of low-melting metals. As a rule, solder contains tin. You can solder with pure tin, but it is expensive and therefore cheap lead is added to the tin. Tin is an environmentally friendly metal and can be used as solder for soldering food utensils and medical instruments in its pure form. If you bend or squeeze a tube made of pure tin, it crunches. The more lead in the solder, the darker the surface of the solder.

Solders are marked with letters and numbers. For example, POS-61, which means P - solder, O - tin, S - lead, 61 - % tin content. POS-61 is the most common, as it is suitable for soldering in most cases. Popularly, POS-61 is often called a tertiary, since it contains a third of lead (Pb).

Solders can be soft or hard. The melting point of soft solders is below 450˚C. Hard solders melt when heated above 450˚C and are not used for soldering with an electric soldering iron.

Main technical characteristics of soft solders
for soldering with an electric soldering iron

The electrical resistivity of tin-lead solder (conductivity) is 0.1-0.2 Ohm/meter, aluminum 0.0271, and copper 0.0175. As you can see, solder conducts current ten times less than copper or aluminum.

The most common solder is POS-61, also called tertiary. It is excellent for soldering and tinning of live parts made of copper, brass and bronze with a sealed seam and is not expensive. Suitable for almost all household soldering situations.

Flux is an auxiliary substance necessary for freeing the surfaces of parts being soldered from oxides and for better spreading of solder over the metal surface during soldering. Without using flux, it is almost impossible to perform high-quality soldering with a soldering iron.

When preparing the most popular fluxes for soldering with an electric soldering iron, rosin is used. It is obtained from the wood of coniferous trees, mainly pine. At a temperature of about 50°C, rosin softens, and at 250°C it begins to boil.

Rosin is not resistant to atmospheric moisture - it hydrolyzes. It consists of 85-90% abietic acid. If you do not remove the remaining rosin after soldering, oxidation of the soldering area occurs. Many people do not know this and believe that rosin is harmless to metal. In addition, by absorbing water from the atmosphere, rosin increases its conductivity and can disrupt the operation of electronic devices, especially their high-voltage circuits.

Popular fluxes for soldering with an electric soldering iron

Flux based on alcohol and solvents must be stored in an airtight container, otherwise the liquid will quickly evaporate. A bottle of manicure polish is very convenient for this purpose. Always have a brush at hand, which is convenient for applying flux to the soldering area.

You can find such a bottle in almost any home. Another advantage is that the brush and twist are not dissolved by alcohol and solvent. Before filling with flux, be sure to thoroughly wash the bottle and varnish brush. If the varnish has hardened too much, pour in acetone and leave.

After a while the varnish will dissolve.

I prepare alcohol-rosin flux in a bottle. First, I pour rosin powder through a paper funnel and then fill it with alcohol. It is easy to pour alcohol into the narrow neck of the bottle if you touch the neck of the bottle with alcohol to a brush previously soaked in alcohol. You need to pour it very slowly and you won’t spill a single drop. Over time, the alcohol evaporates and the flux becomes thick. Then you need to dilute it with alcohol to the required consistency.

As a flux, I often use the undocumented flux of aspirin (acetyl salicylic acid), which is used as a medicine. With its help, you can tin copper and steel surfaces without prior preparation. Liquid flux for soldering with a soldering iron can easily be prepared on the basis of aspirin; just dissolve the tablet in a small amount of alcohol, acetone or water.

Solder pastes (tinol) for soldering

Solder paste (tinol) is a composition of solder and flux. The paste is irreplaceable when soldering with a soldering iron in hard-to-reach places, and when installing unframed radio components. The paste is applied with a spatula in the required amount to the soldering area and then heated with an electric soldering iron. The result is a beautiful and high-quality soldering. Its use is especially convenient if you have no experience working with a soldering iron.

You can make your own pasta. To do this, you need to select a brand of solder suitable for soldering the required metal. Next, use a file with a large notch to cut sawdust from the rod. Then add the liquid soldering flux selected from the table, mixing the sawdust until a paste-like composition is obtained. The paste should be stored in an airtight container. The shelf life of the paste is no more than six months, since solder filings oxidize over time.

Source: https://YDoma.info/tehnologii-remonta/kak-payat/kak-payat-pripoi-flyusy.html

Solders

Radio electronics for beginners

At the beginning of their amateur radio activities, many novice radio amateurs rarely ask themselves about the types of solders and what their properties are.

To assemble the simplest homemade devices, the most common POS-61 or similar is sufficient. As they say: “It would be something to solder with”

You don't even have to buy solder. It is enough to take an old printed circuit board from some electronic device and assemble it with a heated soldering iron tip from the soldered contacts.

This method of “extraction” is especially relevant for those who live far from cities and large populated areas, where there is no opportunity to visit a radio store.

Solder collected from printed circuit boards

But still, solder to solder is different. In his practice, a person dealing with electronics must understand the issue of his choice. Therefore, we will consider in detail what types of solders there are, what they are used for, which one is better to use for installing electronic circuits and repairing household radio equipment.

What types of solders are there?

Solders are divided into soft (low-melting) and hard. For the installation of radio equipment, low-melting ones are used, i.e. those whose melting temperature ranges from 300 to 4500C. Soft solders are inferior in strength to hard solders, but they are used for assembling electronic devices.

Solder is an alloy of metals. For low-melting solders, this is usually an alloy of tin and lead. It is these metals that make up the majority of the alloy. Alloying metals may also be present in it, but their quantity in the composition is small. Impurities of other metals are introduced into the alloy to obtain certain characteristics (melting point, ductility, strength, corrosion resistance).

The most widely used type of solder is POS (Tin-Lead Solder). Next, a brief designation of its brand is followed by a number that shows the percentage of tin in it. So POS-40 contains 40% tin, and POS-60, respectively, 60%.

It happens that solder of an unknown brand comes into use. Its composition can be roughly assessed by indirect signs:

• Solders of the tin-lead group have a melting point of 183 – 2650C.
• If the solder has a bright metallic sheen, then it has a fairly high tin content (POS-61, POS-90). And, conversely, if it is dark gray in color and the surface is matte, then this indicates a high lead content. It is lead that gives the surface a peculiar grayish tint.
• Solders containing a lot of lead are very ductile. For example, a solder rod with a diameter of 8 mm. with a high lead content (POS-30, POS-40) is easily bent by hand. Tin, unlike lead, gives the alloy strength and rigidity. If there is a lot of tin in the alloy, then it will no longer be possible to bend such a rod easily.

POS-40 (bar)

Let's consider the purposes for which solders of the tin-lead group (POS) are used.

• POS-90 (Sn 90%, Pb 10%). Used for repairing food utensils and medical equipment. As you can see, it contains a small lead content (10%), which is quite toxic and its use in things that come into contact with food and water is unacceptable.
• POS-40 (Sn 40%, Pb 60%). Mainly used for soldering electrical equipment and parts made of galvanized iron, used for repairing radiators, brass and copper pipelines.
• POS-30 (Sn 30%, Pb 70%). It is used in the cable industry, and is also used for tinning and soldering zinc sheets.
• And finally, POS-61 (Sn 61%, Pb 39%). Same as POS-60. I don't think there's much difference between them.

POS-61 is used for tinning and soldering printed circuit boards of radio equipment. It is mainly used as a material for assembling electronics. Its melting point starts at 1830C, and complete melting is achieved at a temperature of 1900C.

Soldering with such solder can be done using a conventional soldering tool without fear of overheating of the radioelements, since its complete melting is achieved already at 1900C.

POS-30, POS-40, POS-90 completely melt at temperatures of 220 – 2650C. For many radio-electronic components, this temperature is subcritical. Therefore, it is better to use POS-61 for assembling homemade electronic devices.

A foreign analogue of POS-61 can be considered Sn63Pb37 (63% tin, 37% lead). It is also used for soldering radio equipment and for making homemade electronics. Radio amateurs choose it as an alternative to the domestic POS-61.

As a rule, any solder is sold in coils or tubes of 10 ~ 100 grams. The composition of the alloy is indicated on the packaging, for example, like this: Alloy 60/40 (“Alloy 60/40” - also known as POS-60). It has the shape of a wire of different diameters (from 0.25 to 3 mm).

It is also not uncommon that it contains flux (FLUX), which fills the core of the wire. flux is indicated as a percentage (usually from 1 to 3.5%). This form factor is very convenient. During operation, there is no need to separately supply flux to the soldering area.

One of the varieties of POS solders is POSSu . Yes, if you say it out loud, it doesn’t sound very presentable.

But, despite this, tin-lead solder with antimony (this is how the abbreviated designation stands for) is used in the automotive industry, in refrigeration equipment, for soldering the windings of electrical machines, elements of electrical equipment, winding parts and cable products. Well suited for soldering galvanized parts. In such an alloy, in addition to lead and tin, there is from 0.5% to 2% antimony.

Solder	Initial melting t0 (Solidus)	Full meltdown (Liquidus), t0
POSSu-61-0.5	183	189
POSSu-40-2	185	229
POSSu-40-0.5	183	235
POSSu-30-2	185	250
POSSu-30-0.5	183	255

As we can see from the table, POSSu-61-0.5 solder is most suitable for replacing POS-61, since it has a complete melting temperature of 1890C.

It is worth noting that there is also a completely lead-free tin-antimony solder POSu 95-5 (Sn 95%, Sb 5%). Its melting point is 234 – 2400C.

Low temperature solders

Among the solders, there are also those that are designed specifically for soldering components that are very sensitive to overheating. The most “high-temperature” among low-temperature ones is POSK-50-18 . It has a melting point of 142–1450C. POSK-50-18 contains 50% tin and 18% cadmium. The remaining 32% is lead. The presence of cadmium in the alloy increases corrosion resistance, but also makes it toxic.

Next in decreasing melting temperature is the ROSE alloy (Sn 25%, Pb 25%, Bi 50%). Marked as POSV-50 . Its melting point is lower than the boiling point of water and is 90 – 940C. It is designed for soldering copper and brass. In the composition of the ROSE alloy, tin occupies 25%, lead – 25%, bismuth – 50%. The percentage of metals in the alloy may vary slightly. Usually indicated in the “Composition” column on the packaging.

This alloy is very popular among radio mechanics and, in general, among all electronics engineers. It is used for dismantling/installing elements sensitive to overheating. Among other things, this alloy is ideal for tinning copper tracks of a newly manufactured printed circuit board.

Finds application in protective fuses that can be found in any radio equipment.

An even lower temperature alloy is WOOD (Sn 10%, Pb 40%, Bi 40%, Cd 10%). Its melting point is 65 – 720C. Since the WOOD alloy contains cadmium (10%), it is toxic, unlike the ROSE alloy.

It is worth noting that ROSE and WOOD alloys are quite expensive.

Solder paste

Source: https://go-radio.ru/solder.html

Melting temperature of solder

The main consumable material during soldering is solder. This is the metal alloy that is fused onto the surface of the base material. But it does this in such a way as not to melt the place where the soldering occurs.

This is achieved due to the fact that the melting temperature of the solder is lower. This parameter is one of the fundamental ones when determining characteristics, when choosing a brand for surfacing and other nuances of use.

After all, according to this parameter, the main classification occurs, which distinguishes soft and hard solders.

Solder for soldering

Soft ones include all those that melt at a value below 300 degrees Celsius. As a rule, these are all those things that are used at home, since they can be dealt with with ordinary tools.

The quality of their connection is not always as good as that of representatives of the other group, but ease of use and improved adhesion often compensate for this. Solids include those in which melting occurs at levels above 300 degrees Celsius. These are more difficult to work with, since they require not only a special flux, but also special tools.

Some of these materials melt at temperatures above 700 degrees, so an ordinary soldering iron is not enough and a more powerful burner is needed.

Soft solder with a melting point below 300 degrees Celsius

It is worth noting that there are several values ​​in this parameter. There is an initial melting temperature, at which the material just begins to transform into a liquid state, and there is a final melting point, at which the alloy completely becomes liquid. For soldering, the first option is taken, as it helps to maintain the viscosity of the material, which makes the work easier and more convenient.

Properties

It is worth noting that many of its properties depend on the temperature at which solder melts. This is due to the composition, because if it contains refractory metals, which in their pure form have high strength, then when added to the alloy they retain these qualities, albeit not fully.

Thus, the direct dependence of the strength of the connection on the melting point is almost always correct. A simple example is Wood's alloy, which is one of the lowest melting options.

In practice, it turns out to be very fragile and can crack or fly off from small temperature influences.

Here there is a dependence on what temperature the resulting compound will withstand. The melting point of the solder must be lower than that of the base metal, otherwise it would already be a welding process.

Soldering with high-temperature solders itself occurs at high temperatures, and accordingly, the connection will better resist such effects.

The thermal conductivity of the solder is also an important factor, because if it is at a low level, it helps to better withstand high temperatures and protects the part from overheating.

Melting temperature of solders

Differences in temperature can be very large, as can be seen in the table example. Moreover, this applies even to neighboring brands in the same series, since much is determined by the additives in the composition and other nuances. Here is the basic data for the most common brands:

Solder name	Melting point, degrees Celsius
Wood's alloy	70
Alloy Rose	90
PSRZI	141
POSI 30	170
AKP	235
PSR 1.5	280
PSR 2	248
POS 50	245
POS 61	192
POS 10	299
POS 40	238
POS 61	190
O2	232
POSSU 95-5	240

Temperature Recommendations

The melting point of soft solders, although it does not exceed 300 degrees, while in hard grades the spread is much greater, still, even in this case the difference is more than three times. Thus, it is worth selecting heat treatment tools that have the power required to achieve the desired parameters.

A higher or lower temperature may not be suitable, so this may be one of the reasons why the solder does not stick to the soldering iron. Deviation when choosing a temperature regime is allowed within small limits, about 10-20 degrees Celsius, preferably in a higher direction.

After all, it is not always possible to accurately set operating parameters, especially on simple soldering irons.

The possibility of a harmless increase in the temperature of the tool is due to the fact that the solder has an initial melting point when it flows from solid to liquid. At this time, the liquid becomes relatively viscous and plastic enough for use. This is followed by the second melting point, when the material already becomes as liquid as possible. It’s already more difficult to work here, so the choice of mode should be just between these two indicators.

Source: https://svarkaipayka.ru/material/pripoj-dlya-payki/temperatura-plavleniya-pripoya.html

Which solder to choose for soldering: types, brands and characteristics

In the manufacture and repair of electrical equipment, skills in handling a soldering iron are constantly required, and solder and rosin are used for soldering; in the middle of the last century, tin was used for these purposes, but not in its pure form, since this is a very expensive pleasure, and alloys with other fusible materials metals.

Which ones are there?

What is solder and how to choose it correctly - in practice they can be soft or hard . Installation of any radio-electronic equipment occurs using low-fusible options.

Components of unknown origin differ in the following characteristics:

1. The rich shine of the cut indicates a high presence of tin.
2. The predominance of lead guarantees the substance a dull gray color and a matte surface.
3. With an increased lead content, the product becomes plastic; for example, a wire with a cross-section of 6 mm is bent by hand without visible effort.

Sometimes, for high-quality soldering, a ready-made mixture is used - this is solder in the form of a wire, and the flux is sealed inside. Manufacturers produce similar substances with flux tolerance within 1-3% of the total weight, which has a beneficial effect on the soldering process and increases labor productivity, since there is no need to constantly dip the soldering iron tip into a jar of flux.

Based on consistency, they are available in two types: soft or hard solder, and based on the melting point, ordinary and refractory types are distinguished.

Solder wettability

This term means the adhesion of molecules of a liquid melt to a solid surface, the degree of which determines the fluidity of soldering . For good soldering, liquid solder qualitatively wets the surface where soldering occurs, and its boundary forms an acute angle.

Dried flux can only be removed by mechanical cleaning, because additional alloy has appeared. If a drop of molten substance forms an obtuse angle with the surface, then this indicates unsatisfactory wetting quality, which is counteracted by dirt, grease stains or a metal oxide film.

Options for wettability of soldering surfaces with molten flux.

Melting temperature

The main criterion for choosing high-quality alloys is that they must come into a liquid state earlier than the structures being joined , and the melting point of the solder differs significantly from that of another type, for example, those containing lead impurities.

The presence of different impurities affects the ability to melt at the same temperature, for example, POS-40 melts when it reaches 238 0C, but there are refractory solders and special devices are used for their melting.

Low temperature options

In first place is the VUDA alloy with the composition: 10% Sn and Cd each, 40% Pb and Bi, the beginning of the melt is 65-72 0C. The second position is occupied by a solder called ROSE, which begins to melt at 90-94 0C. Consists of: 25% tin and lead each, and the remaining 50% is bismuth. The above alloys are expensive solders.

The third place among low-temperature products is occupied by POSK-50-18, with a temperature of 142-145 0C. This solder contains 50% tin, 32% lead and 18% cadmium, which enhances corrosion resistance but adds toxicity.

The second nominee (called ROSE) is very popular among radio amateurs, but in domestic radio electronics its marking is POSV-50, where the numbers are the percentage of bismuth. Used for installation/dismantling and tinning of overheat-sensitive copper tracks on printed circuit boards.

Soft look stamps

Solder for soldering in this category is used with a ready-made flux located inside the wire, so melting occurs simultaneously . A product called Tretnik has become widespread because it contains a third of the lead of the total composition. Tin, which is part of the alloy for soldering, is environmentally friendly, so it is allowed to use this type in the food industry.

Soft types of solders are used for soldering parts that are afraid of overheating, for example: transistors or fuses. Due to its toxicity, WOOD alloy is used in limited areas of human activity.

Domestic alloys are marked with the abbreviation POS, but if there are other substances, a letter corresponding to the name is added at the end, for example, POSV-33 - this solder contains equal parts of tin, lead and bismuth.

Main technical parameters

Soldering materials are divided according to the following parameters:

1. Conductivity , for example, solders containing aluminum have better similar values ​​than those marked PIC.
2. Tensile strength , unit kg/mm. This parameter directly depends on the percentage of tin.
3. Melting point , which depends on the chemical composition.

Table of temperature and application depending on the chemical composition of the solder.

Flux

Solder with rosin in the form of a hollow wire twisted into rings is common on sale . A flux of similar composition is made from coniferous trees; such a substance becomes soft when heated to 50 ° C, and at 250 ° C it begins to boil with partial evaporation. Rosin must be removed after finishing work, otherwise oxidation will occur, and the substance, absorbing moisture from the air, will begin to interfere with the proper operation of the devices.

Popular formulations

There are three main categories:

1. Light-colored rosin is used when joining copper and other soft non-ferrous metals; an alcohol solution with a concentration of one to five is used in a hard-to-reach area of ​​adhesion; and a mixture of glycerin and rosin is used for hermetic soldering.
2. Fluxes containing alcohol, petroleum jelly or zinc chloride are used to permanently bond non-ferrous and precious metals. The use of paste is justified by the fact that it is more convenient to apply it in the required quantity to the product.
3. Acid-active substances are produced in liquid form, for example, orthophosphoric acid, which has a density of 1.7.

Pasty

Tinol paste has become widespread and is used for soldering various products in hard-to-reach places. It is applied with a spatula, followed by active heating with a soldering iron or other, more powerful electric tool. Often used by inexperienced performers who do not have the skills to work with tin and rosin.

Using PIC

The discoverers of this alloy were pleasantly surprised that it turns into a molten state at a lower temperature, and the eutectic mixture can act as a solvent for the added metal. This is how the very first brands of POS solders were developed.

Lead options

Such mixtures containing lead are characterized by softness, rapid melting and easy processing, which is why they are called lead-containing solders. They are harmful and have been banned for use in soldering electrical components around the world . The percentage of cadmium, mercury, and similar harmful components in equipment is strictly regulated and verified by relevant organizations.

Lead free

Lead-free solder must not contain harmful metals and is considered environmentally friendly, not causing harm to the environment and the solder performers. The simplest example is tin solder, which contains pure tin, has increased wettability and high electrical conductivity. To combat deficiencies, copper, silver and gold are added to them, which helps make the substance harder.

Such a product has an increased melting temperature, but it has not yet been possible to find a complete alternative to standard types of solder, but the main indicator is harmlessness. Tin occupies a major place in the chemical composition, so its inherent properties have a great influence on the solder, because of this, the melting point of lead-free solder is lower, and the material is softer.

Colophon resin

This is the name of the well-known rosin - an amorphous substance with a characteristic fracture and glassy sheen when chipped . In addition to the fact that it has a natural dielectric property, the following features are known:

• dissolves well in gasoline, alcohol, ether and acetone, but remains indifferent to the effects of water;
• the melting point varies between 50-70 degrees, but sometimes rises to 130 0C;
• the chemical composition contains up to 90% resin acids, the basis is abietic acid;
• easily destroyed with minor mechanical impact.

The color varies from light yellow to dark brown shades, which depends on the degree of purification and indicates the amount of foreign impurities. Excellent electrical insulating properties belong to lemon-colored resin.

Secrets of choice

The task of any performer is to create a strong and reliable fastening of radio components to the board, therefore the selection of solder is carried out according to the following parameters:

1. The composition of materials to be soldered - here it is necessary to take into account the characteristics of the material, its ability to overheat and much more.
2. When soldering wires or other large objects, refractory solders are used.
3. Sometimes it is necessary to use solder that has a high ability to conduct electric current; it must be taken into account that the resistance of tin is much lower than that of lead, therefore expensive brands of solder are used for soldering high-frequency circuit boards.

In each specific situation, the performer must clearly know the correspondence of the solder and the product being connected in order to choose the best option for high-quality soldering.

conclusions

Today there is an abundance of different solders on sale, as they say, for all occasions, but you should choose proven samples that will help solder the product with high quality and with high reliability during operation.

Source: https://svarka.guru/payka/oborudovaniya/pripoy.html

Melting temperature of solder: features and types of solders

In the modern world, soldering is usually called a process that makes it possible to obtain a permanent connection of several metal parts, where the connecting material is already molten metal, which must melt at a lower temperature than the metal material from which these parts are composed.

This intermediate molten metal is called an alloy, and the process itself is called solder. Depending on the melting temperature, different types of soldering are distinguished: low-melting and refractory. Thus, low-melting solders melt at temperatures below four hundred degrees, and refractory solders melt at temperatures from five hundred to 1100 degrees.

Usually in brands, solder is denoted as PIC, and this abbreviation stands for: tin-lead solder. If there is also some number nearby, then this figure usually indicates what percentage of tin content is in the composition.

Solder classification

The class of solder depends on the melting temperature:

1. Soft solder is achieved by melting up to four hundred degrees Celsius.
2. Brazing solder is achieved by melting above five hundred degrees Celsius.
3. Semi-solid solder is achieved by melting anywhere from molten tin to four hundred degrees Celsius.

Solders of the soft and semi-hard classes are strong at tensile strength from fifty to seventy Megapascals; they are intended for soldering conductive parts of machines. They are made by using a soldering iron or by dipping the parts to be soldered into liquid solder.

Hard solder is strong up to five hundred Megapascals, used as the number one strength category solder for soldering conductive parts with high heating and parts with major mechanical load. This type of solder is produced using electrodes made of copper or graphite. Small parts are soldered using an autogen.

Advantages of soft and semi-hard solders

The main areas of application for soft and semi-hard solders are the following:

1. POS63 – for soldering collectors, sectional armatures, windings with H insulation of an electrical machine.
2. POS61; POSSu61-0.5 and POS61M are necessary for soldering copper elements and its alloys, as well as silver and nickel parts and conductive parts of an electric machine, with operating temperatures up to one hundred and sixty degrees Celsius.
3. POS40 and POSSU40-0.5 - are intended for soldering copper elements and its alloys, as well as steel and metals with tin, silver or nickel coating, collector bands and sectional armatures of machines that come into contact with salty liquid (for example, sea water ).
4. POSSUZO-0.5 - in order to solder copper elements and its alloys, as well as elements made of iron and stainless steel, as well as soldering cables, bandages, parts of devices that will operate at temperatures up to one hundred and sixty degrees Celsius.
5. POSK50-18 - in order to solder copper elements and its alloys that can withstand overheating, as well as soldering parts made of aluminum and copper, ceramic, glass and plastic parts with the addition of tin, silver, nickel components.
6. POS10 and POSSu18-0.5 – for soldering contact surfaces of electrical devices, relays and other machine components.
7. P0SSu95-5 and PSrZKd - for soldering collectors, sectional armatures, bandages and conductive connections of pipelines and electrical equipment.
8. POSIZO and PSrZI - are designed to solder copper elements and its alloys, parts made of non-metallic materials and glass. They have high fluidity and provide a reliable connection of parts during soldering.

Antimony solders are not intended for use in soldering parts containing zinc or galvanized steel.

Advantages of Brazing Solders

Advantageous applications of brazing alloys:

1. PSr72 and PSr50 – for soldering metal-ceramic contacts and various conductive parts that must withstand impacts and bending.
2. PSr45 - in order to solder copper elements and its alloys, as well as stainless steel parts, rotor windings and windings of loaded electrical devices. This solder gives greater density, and at the same time greater strength of the resulting joints.
3. PSr25 – for soldering copper elements or parts from its alloys, stainless steel parts. It is a substitute for PSr45 when creating simple adhesions.
4. PSr71 - for soldering the same parts as PSr72, but is used when high fluidity is required.
5. PSr25f; PSr15 and PMF7 - for soldering copper or copper alloy parts, parts of devices that conduct current, which should not withstand bending and impacts.
6. L63 and LOK59-0.1–0.3 - for soldering copper parts or cast iron parts. This soldering is very strong and suitable for difficult bending and impact conditions.
7. PZHL500 – soldering of parts, with operating temperatures up to six hundred degrees Celsius.

Four secrets of soldering

In order to solder well and correctly, one tool is not enough. You also need to know some secrets that would allow you to master the soldering technique to perfection. It’s probably worth revealing a few of these secrets.

So, the first secret is to correctly use solder and flux for soldering. The second important secret of soldering is maintaining the cleanliness of the tip and the soldering iron itself and, of course, its heating. There are many ways to clean a sting. Use one of them and then your work will go just fine.

The third secret is also important when soldering: the cleanliness of the objects being soldered. The fourth rule, which any master needs to understand, is simple but necessary: ​​connect the wires correctly when soldering and do a good warm-up of the places where the parts will be soldered at a certain melting temperature.

And, of course, when working with such equipment, you should always take precautions. So, it is necessary to solder not at one point, but try to do it at some distance from each other. Do not twist the ends of parts around the conductor at melting temperature.

It is always worth remembering that when soldering, even at the lowest melting point, tin and lead vapors are released. They are very dangerous and harmful to the human body. Therefore, you should never lean over the place where soldering occurs, no matter what the melting temperature is.

After all, no matter what the melting temperature of the solder, the fumes will still be harmful and will cause irreversible harm to the human body. If you decide to solder in the summer, then do it either in an open space, or, if possible, near an open window. The main rule for such soldering is to ventilate the room well. And when the work is finished, you will also need to thoroughly wash your hands using soap.

Source: https://stanok.guru/oborudovanie/raznoe/osobennosti-temperatury-plavleniya-pripoya.html

All about POS solder

Greetings to dear readers! In this material I tried to collect all the data about PIC solder. This Tin-Lead Solder is the most popular solder for mounting radio components and is used more often than others in radio engineering. I will try to explain why this is so and tell you about the types and technical characteristics of POS series solders. I’ll also tell you a terrible secret about POS-60 and POS-62 solders. Go!

Types of POS solders

First, let's remember what types of solders are made from alloys of the tin-lead group. The most popular are antimony-free solders POS-10, POS-40, POS-61 and POS-90. POS solder containing antimony is called POSSU. Antimony in the solder adds several percent to its strength.

When we talk about melting a mixture of tin and lead, we need to remember the definitions of solidus and liquidus . When any mixture of two or more metals is heated, the melting (transformation from solid to liquid phase) of the lightest particles occurs first. This temperature mark is called the solidus of the alloy.

With a further increase in temperature, more refractory components begin to melt. As soon as they melt, the liquidus . The PIC solder is now completely melted. This process is explained in more detail by a picture taken from a presentation on the topic of alloys.

Between these two points is a state of increased ductility of the solder . In this state, the solder can be pulled and deformed without losing integrity.

There are eutectic alloys - solders, in which the solidus and liquidus points coincide. This is very convenient when soldering and indicates the high quality of the solder.

About the composition of solder

The name of the solder of the tin-lead group indicates the tin content in it. For example, POS-40 contains 40% tin, and POS-61 contains almost 61% tin. The rest consists of lead and additional impurities.

By appearance, you can estimate the composition of the solder by eye. If the PIC solder is more matte and dark, then it contains more lead. If it is lighter and shiny, then there is more tin. This is best understood by comparison.

Look at the photo to see what a sheet of tin and a sheet of lead look like.

The strength of solder depends not only on the alloy alloy, but also on the metal being soldered. For example, to solder copper or zinc, several percent of copper or zinc are added to the POS solder, respectively. This reduces chemical erosion of the metal and increases the surface strength of the joint.

Solder alloying

To improve performance characteristics, alloying of solder with the following substances is used:

• adhesion is improved by the addition of copper, cadmium, antimony, aluminum, silver and zinc;
• ductility and resistance to thermal cycling are improved by the addition of indium, silver, manganese, bismuth, and lithium;
• Nickel, cobalt, zinc, silicon, boron, iron add strength
• The corrosion resistance of solder is increased by nickel and copper;
• Heat resistance is increased by silicon, zirconium, tungsten, vanadium, cobalt, niobium, hafnium.

Technical characteristics of POS and POSSu solders

In order not to describe all the technical characteristics of solders of the tin-lead group, I will simply provide a table of parameters. It can be used to determine the melting point, density, electrical resistivity, thermal conductivity, tensile strength, elongation, impact strength and Brinell hardness of solders.

Analysis of the table shows that the most fusible among the list is cadmium solder POSK 50-18 with a melting point characteristic of 145 degrees Celsius. The strongest solder is POSSu 4-6 solder with a tensile strength of 6.5 kgf/sq.m. mm.

Technical characteristics of POS-10 solder

POS 10 solder has a distinctive chemical composition. It contains 9-10% tin, about 89% lead, 0.2% bismuth, 0.1% antimony and other impurities in small quantities. POS-10 solder is used for soldering and tinning contact surfaces of electronics. For example, they solder relays and fill control plugs in radio electronics housings.

The POS-10 soldering temperature is 299 degrees Celsius. The solidus point is 268 degrees.

Advantages of POS-10 solder:

• high melting point is useful when soldering equipment cases.

Disadvantages of POS-10 solder:

• low strength and tensile strength of about 3.2 kgf/sq.mm.;
• high resistivity - 0.2 Ohm x sq.mm./m;
• high content of lead, which is hazardous to health.

Technical characteristics of POS-30 solder

Solder for soldering of the POS 30 brand is an intermediate link between POS 10 and POS 40. The composition of POS 30 solder is as follows: 30% tin and 69.5% lead. The rest is impurities and doping.

Solder POS 30 can be easily replaced with POS 40, which is described below. The melting point (liquidus) is 238 degrees, and the plasticity temperature (solidus) is 183 degrees Celsius.

According to the technical characteristics, POS 30 solder is most often used for soldering and tinning of zinc sheets and radiators.

Advantages of POS-30 solder:

• good adhesion;
• high strength.

Disadvantages of POS 30 brand solder:

• high lead content;
• often produced in rods.

Technical characteristics of POS-40 solder

According to the chemical composition, POS 40 solder consists of 39-41% tin, 59% lead. The remaining impurities are in the same ratio as in POS-10. Soldering solder POS-40 is often used for soldering and tinning radio equipment casings made of galvanized iron with galvanized seams.

The soldering temperature of POS-40 solder is 238 degrees Celsius, and the solidus is 183 degrees.

Advantages of POS-40 solder:

• good ratio of ductility and melting point;
• because of this, it tolerates thermal cycling better than POS-61.

Disadvantages of POS-40 solder:

• high lead content, which is harmful to health;
• elevated liquidus temperature.

The terrible secret of POS-60 solder

Now the time has come for the terrible secret of POS 60 solder . According to GOST 21930-76 entitled “Tin-lead solders in ingots. Technical specifications" and GOST 21930-76 "Tin-lead solders in products. Technical specifications", solder such as POS-60 simply does not exist. download and view GOST 21930-76 itself . Here is the complete table from this GOST.

So “ POS-60 ” is jargon or a popular designation for “the solder that everyone solders with.” It seems to me that this is due to confusion in the designation of POS-61. Because when the tin content in the solder according to GOST is from 59 to 61%, it is more logical to call it POS-60 rather than POS-61.

Among the solders produced according to international standards there is Sn60Pb40 solder . This is a solder solder containing 60% tin and 40% lead. It could be called POS-60, if at least specifications for it were developed. According to international data describing the characteristics, the melting point of 60/40 solder is 191 degrees Celsius.

The same story with POS-62 type solder . Such lead solder according to GOST has not yet been invented. So, if they ask me “what is the melting temperature of POS-62 solder,” I know that the answer with the figure 184 degrees Celsius must be looked for in the imported solder catalog. For example, you can use the Kester solder catalog.

Technical characteristics of POS-61 solder

The designation of POS-61 brand solder, as we found out, is quite controversial, but you can’t argue against GOST. POS-61 is used for soldering and tinning of electronic components and printed circuit boards of precision instruments with highly hermetic seams, for which overheating is not allowed.

Composition of POS-61 solder

The chemical composition of POS-61 solder is as follows:

• Tin 59 - 61%;
• Antimony - no more than 0.1%;
• Copper - no more than 0.05%;
• Bismuth - no more than 0.02%;
• Arsenic - no more than 0.02%;
• Iron - no more than 0.02%;
• Nickel - no more than 0.02%;
• Sulfur - no more than 0.02%;
• Zinc - no more than 0.002%;
• Aluminum - no more than 0.002%;
• Lead - everything else - about 38.7 - 40.7%.

The soldering temperature of POS-61 solder is 220 degrees

Source: https://masterpaiki.ru/vse-pro-pripoy-pos.html

Melting temperature of tin for soldering, POS-40 and POS-60 solder, technical characteristics

Solder is a metal or mixture of metals used in soldering to join parts together. Typically, alloys based on tin, copper and nickel are used. Tin-based solder is included in the group of low-melting solders.

And the melting temperature of the solder here does not exceed 450 °C. These compounds are widely used to work with radio equipment.

Solders based on tin and lead are very common; they are widely used in our metal industry: the abbreviation POS.

To assemble homemade devices of the simplest design, the most common solder POS-61 or similar is sufficient. The alloy can be obtained from an old printed circuit board from an electronic device and assembled with a soldering iron from the soldered contacts.

Types and characteristics of solders

They are soft (low-melting) and hard. For installation of radio equipment, low-melting materials are used, with a melting point of 300−450 °C. Soft solders are inferior in strength to hard solders, although they are the ones used for assembling electrical appliances.

Low-melting alloys are usually an alloy of lead and tin primarily. There are few alloying elements.

Impurities of other metals are introduced to obtain certain characteristics:

• plasticity;
• melting point;
• strength;
• corrosion resistance.

The number in the brand designation indicates the percentage of tin it contains. So, the technical characteristics of POS-40 solder are such that it contains 40% Sn, and POS-60 - 60%.

If the brand is unknown, the composition can be assessed by indirect signs:

• The melting point of POS is 183−265 °C.
• If the solder has a metallic sheen, it means there is a lot of Sn in it (POS-61, POS-90). If the color is dark gray and the surface is matte, this indicates a high lead content, which is what gives the grayish tint.
• Solders containing large amounts of lead are very ductile, and tin imparts strength and rigidity.

Use of tin-lead group alloys

These alloys include the following:

• POS-90 contains: Pb - 10%, Sn - 90%. Used for repairing medical equipment and food utensils. There is little toxic lead, as it should not come into contact with food and water.
• POS-40: Pb - 60%, Sn - 40%. Mainly used for soldering electrical equipment and galvanized iron products; it is also used to repair radiators, brass and copper pipelines.
• POS-30: Sn - 30%, Pb - 70%. Used in the cable industry, for soldering and tinning and zinc sheeting.
• POS-61: Pb 39%, Sn 61%. Like with POS-60. There's not much difference.

Using POS-61, tinning and soldering of printed circuit boards of radio equipment is carried out. This is the main material for assembling electronics. It begins to melt at 183 °C, complete melting at 190 °C. You can solder with this solder using an ordinary soldering iron without fear that the radioelements will overheat.

POS-30, POS-40, POS-90 melt at 220−265 °C. For many radio-electronic elements this temperature is subcritical. It is better to assemble homemade electronic devices with POS-61, whose foreign analogue can be considered Sn63Pb37 (where Sn is 63% and Pb is 37%). It is also used to solder radio equipment and homemade electronics.

Solders are usually sold in tubes or coils of 10-100 g. The composition of the alloy can be read on the packaging, for example: Alloy 60/40 (“Alloy 60/40” - POS-60). It looks like a wire with a diameter of 0.25-3 mm.

It often contains flux (FLUX), which fills the core of the wire . indicated as a percentage and amounts to 1−3.5%. Thanks to this form factor, there is no need to supply flux separately during operation.

A variety of POS - POSSu is a tin-lead alloy with antimony, and is used in the automotive industry, in refrigeration equipment, for soldering electrical equipment elements, electrical machine windings, cable products and winding parts; Suitable for soldering galvanized parts. In addition to lead and tin, the alloy contains 0.5−2% antimony.

As the table shows, POSSU-61−0.5 is most suitable for replacing POS-61, because its complete melting temperature is 189 °C. There is also a completely lead-free , tin-antimony POSu 95−5 (Sb 5%, Sn 95%) with a melting point of 234−240 °C.

There are solders designed specifically for soldering parts that are highly sensitive to overheating. The most “high-temperature” among low-temperature ones is POSK-50−18 with a melting point of 142−145 °C. POSK-50−18 contains 8% cadmium, 50% tin and 32% lead. Cadmium enhances corrosion resistance, but at the same time imparts toxicity .

In descending order of temperature comes ROSE (Sn 25%, Pb 25%, Bi 50%), marked POSV-50. T pl. - 90−94 °C. Designed for soldering brass and copper. This alloy contains 25% tin, 25% lead, and 50% bismuth.

The ratio of metals in percentage may vary slightly, and their quantity is usually indicated on the package in the “Composition” column. This solder is extremely popular among electronics engineers. Used when dismantling/installing elements sensitive to overheating.

Among other things, the alloy is ideal for tinning the copper tracks of a brand new printed circuit board.

Used in protective fuses in radio equipment.

An even lower temperature WOOD alloy (Sn 10%, Cd 10%, Pb 40%, Bi 40%). Melting point - 65−72 °C. Since the alloy contains 10% cadmium, it is toxic, unlike ROSE.

Both ROSE and WOOD are quite expensive solders.

Types of Tin-Lead Solders (POS)

The most famous of the solders are POS 10, POS 40, POS 61 and POS 90 (antimony-free solders). And POS containing antimony is called POSSU . antimony increases the strength of the solder by several percent.

If we are talking about melting a compound of tin and lead, you need to know the definitions of solidus and liquidus . If you heat any mixture of two or more metals, the melting (transformation from solid to liquid state) of the lightest particles will occur first. This is the temperature point called the solidus of the alloy.

With further heating, the more refractory metals in the alloy begin to melt. After they melt, the liquidus . After which the PIC solder is considered completely melted.

Between the solidus and liquidus points there is a state of increased ductility of the solder . At this temperature, the solder can be deformed and pulled without losing integrity.

There are solders in which the solidus and liquidus points coincide , they are called eutectic alloys . This indicator indicates that the solder is of high quality; such solder is very convenient for soldering.

About the composition of the PIC

POS-40 contains 40% tin, and POS-61 contains about 61% tin. Everything else is lead and additional impurities. By appearance you can determine what kind of solder you have in front of you. Matte and dark solder contains more lead. Light and shiny - more tin. This can best be seen in comparison.

The strength of the solder depends, along with the alloying of the alloy, on the metal being soldered. To solder zinc or copper, a little zinc or copper is added to the POS, respectively. This reduces chemical erosion of the metal and increases the surface strength of the joint.

Alloying POS

Solder performance can be improved by doping with the following substances:

• Plasticity and resistance to thermal cycling are improved due to the addition of silver, indium, lithium, manganese, and bismuth.
• corrosion resistance is improved by nickel and copper.
• Cobalt, silicon, zirconium, hafnium, vanadium, tungsten, and niobium contribute to increasing heat resistance
• Solder becomes stronger if you add boron, iron, nickel, cobalt, zinc, and silicon.
• The addition of silver, copper, zinc, cadmium, antimony and aluminum improves adhesion .

Characteristics of POS and POSS

The characteristics of solders of the tin-lead group are shown in the parameters table. Here you can see such characteristics as electrical resistivity, melting point, tensile strength, density, impact strength and Brinell hardness, thermal conductivity, relative elongation of existing varieties of POS and POSSU.

The table shows the lowest melting point solder (cadmium POSK 50-18) with a melting point of 145 °C, and the strongest solder for soldering (POSSu 4-6) with a tensile strength of 6.5 kgf/mm2.

Characteristics of POS 10

POS 10 has the following chemical composition: 9-10% tin, about 89% lead, 0.2% bismuth, 0.1% antimony and other impurities in small quantities. POS-10 is used for tinning and soldering contact surfaces of electronics. For example, it is used to fill control plugs in radio electronics housings and solder relays.

Soldering temperature POS 10 - 299 °C. The solidus point is 268 °C.

Pros of POS 10

• high melting point is useful when soldering equipment cases.

Cons of POS 10

• high resistivity - 0.2 Ohm•mm2/m;
• high content of lead, which is hazardous to health;
• low strength and tensile strength of about 3.2 kgf/mm2.

Characteristics of POS 30

POS 30 is an intermediate link between POS 10 and POS 40. POS 30 consists of: 30% tin and 69.5% lead. The rest is doping and impurities. POS 30 can be replaced without hesitation by POS 40. The melting point (liquidus) is 238 °C, and the plasticity temperature (solidus) is 183 °C. POS 30 is usually used for soldering and tinning of radiators and zinc sheets.

Pros of POS 30

• good adhesion;
• high strength.

Cons of POS 30

• high lead content;
• often produced in rods.

Characteristics of POS-40

POS 40 consists of 39-41% tin, 59% lead. The remaining impurities are in the same ratio as in POS-10. POS-40 is usually used for soldering and tinning of radio equipment casings made of galvanized iron with galvanized seams.

The soldering temperature of POS-40 solder is 238 °C, and the solidus is 183 °C.

Pros of POS 40

• more resistant to thermal cycling than POS-61;
• good ratio of ductility and melting point.

Cons of POS 40

• elevated liquidus temperature;
• high lead content, which is harmful to health.

Pos. 61 (pos. 60)

There are solders produced according to international standards, for example, Sn60Pb40 solder containing 60% tin and 40% lead. The melting point of 60/40 solder is 191 °C.

Another example is POS-62 . Its melting point c is 184 °C; it can be found in a foreign catalog of solders (for example, Kester ).

Characteristics of POS 61

POS-61 is usually used for soldering and tinning of electronic components and printed circuit boards of precision instruments with highly hermetic seams, for which overheating is not allowed.

Composition of POS-61:

• Tin 59 - 61%;
• Antimony - no more than 0.1%;
• Copper - no more than 0.05%;
• Bismuth - no more than 0.02%;
• Arsenic - no more than 0.02%;
• Iron - no more than 0.02%;
• Nickel - no more than 0.02%;
• Sulfur - no more than 0.02%;
• Zinc - no more than 0.002%;
• Aluminum - no more than 0.002%;
• Lead - the rest - about 38.7 - 40.7%.

The soldering temperature of POS-61 solder is 220 °C. Solidus - 183 °C.

Technical characteristics of POS 61 (according to GOST 21931-76):

• Density determines the weight of POS-61 solder and is equal to 8.5 g/cm3;
• The electrical resistivity is 0.139 Ohm•mm2/m;
• Thermal conductivity is 0.12 kcal/cm•s•deg;
• Tensile strength is 4.3 kgf/mm2;
• The relative elongation is 46%.

Pros of POS 61

• good adhesion to metal surfaces;
• universal solder for soldering and most radio installation work;
• the best ratio of melting temperature and strength;
• accessibility and prevalence;
• often produced in the form of wire (POS 61 T2A);
• low cost.

Cons of POS 61

• versatility reduces performance in special cases, for example when soldering zinc;
• melting temperature is not suitable for all devices;
• solder fumes (lead in it) are harmful to health.

Characteristics of POS-63

POS 63 in accordance with GOST and OCT 4G 0.033.200 is an alloy consisting of 63% tin and 37% lead. This is a kind of modernization of POS-61 solder, adjusted to the international standard J-STD 006B. Many high-quality Chinese solders are similarly labeled Sn63Pb37 . These are eutectic alloys with a melting point of 183 °C.

POS-63 is mainly used for soldering and tinning pins of microcircuits and packaged radio components, printed circuit boards, wires and cables. It is the most common of modern solders . The characteristics of POS 63 solder are very similar to POS-61.

Pros of POS 63

• coincidence of solidus and liquidus points;
• the most common POS series solder;
• relatively low melting point;
• low cost;
• supplied in the form of wire filled with flux.

Cons of POS 63

• often counterfeited, especially in China;
• contains lead, which increases the cost of recycling electronic equipment in accordance with modern safety standards.

Characteristics of POSSu-61-0.5

POSSu-61-0.5 designates a type of antimony solder containing 61% tin, up to 0.5% antimony and about 38% lead.
It is used for soldering and tinning of printed circuit boards and galvanized radio components with increased operating temperature requirements. The melting point is 189 degrees. Pros of POSSu-61-0.5

• increased adhesion to the metal surface due to the antimony content;
• characteristics are identical to POS-61.

Cons POSSu-61-0.5

• difficult to find on sale;
• increased cost.

Characteristics of POS-90

POS-90 consists of 90% tin and 10% lead. It also contains about 0.1% antimony and 0.05% copper. Most often used for soldering and tinning internal seams of medical equipment and food utensils . The melting point of POS 90 is 220 degrees.

Pros of POS 90

• low lead content;
• rarely counterfeited;
• low resistance;
• high strength.

Cons of POS 90

• high cost (higher than POS-61);
• low plasticity.

Solder for connoisseurs of high-quality sound

This type of solder is well known to fans of Hi-End electronics . This is solder for soldering audio equipment, produced in the 30s - 50s of the last century. These solders have high purity components, which has a positive effect on the highest quality sound. To hear the effect of such solder, you need both a high-quality sound source, a sound emitter, and excellent hearing.

Experts “listen” the solder and formulate their own alloys for better sound transmission.
The most famous for music lovers is solder from Kester . It sells for $10 per meter. Every year it becomes less and less. Its composition is close to POS-90.

Kester solder is composed of 85.9% tin, 8.5% lead, 3.28% silver, 0.34% copper, 0.79% sodium, 0.55% magnesium and 0.27% mercury.

There is also a solder containing 50% tin and 50% lead Sn50Pb50 .

Buy products based on the article:

Source: https://ampero.ru/news/410480-raznovidnosti-pripoev-olovyanno-svintsovyh-pos.html

Solder POS 61: melting point of tin for soldering, composition and technical characteristics

Most novice radio amateurs who have not encountered soldering before are wondering what solders can be and how they differ from each other.

POS solder is a tin-lead alloy. Depending on the ratio of these elements, there are different markings. The most common is POS 61 solder.

Types of solders

Solder is not always necessary to purchase. You can use an old radio component and assemble it from the board tracks using a soldering iron tip. This option is perfect for those who live far from the city, where it is not possible to purchase the material in a store.

Standard lead solders.

However, they are different and differ in their properties and characteristics. In this regard, every experienced master should understand this issue. To solder parts, it is necessary to use special alloys - solders.

The latter have a lower melting point than individual parts of the products.

Such alloys are divided into two main categories depending on their melting point: soft and hard. The first type is widely used in radio electronics, both by amateurs and professionals.

Low-melting solders include solders with a melting point of less than 450°C. They are made from: gallium, indium, tin, bismuth, lead and cadmium. High-temperature ones melt when heated above 450°C. In any case, it is usually an alloy consisting of several metals and impurities.

The most common option is a tin-lead alloy called PIC. The numbers after the abbreviation indicate the percentage of tin.

You can distinguish one alloy from another without knowing the brand. For example, with a higher tin content, a characteristic metallic luster appears, and with a higher lead concentration, the color becomes dark gray.

In addition, the melting point of POS does not exceed 265°C. Another distinctive feature of alloys with a higher proportion of lead is their ductility and the ability to be easily bent by hand.

Classification of alloys is carried out in accordance with GOST standards.

Physico-mechanical properties of solders.

The most common are:

• solder POS 90;
• POS 61;
• POS 40;
• POS 30.

In fact, there are significantly more markings. There are several dozen of them. Each is written in such a way that the composition of the alloy becomes clear from its name; all are manufactured in accordance with GOST 21930-76 tin-lead solder.

It is worth noting that the alloys differ from each other not only in their chemical composition. Depending on the form of release, they come in ingots, wire, a tube with rosin, or in a rod.

For example, POS 61 solder can be sold in rods or in the form of wire of various diameters. It is important to understand that the ratio of lead to tin affects the melting point. This parameter largely determines the choice of the required alloy.

This flux contains no halogens. Thanks to this fact, it has significantly less harm to the health of masters.

The use of alloys of various grades is determined by the scope of their application. POS thirty and forty are considered soft. Their melting point does not exceed 300°C. Used in joining galvanized products, tinning, repairing electrical appliances, etc.

Bottom line

The melting point of tin makes this material an excellent solder. POS brand solders are particularly widespread. They are used in industry, in private workshops, and by radio amateurs.

Many brands of this solder allow you to choose the necessary alloy, which is ideal for solving almost any problem.

Source: https://tutsvarka.ru/oborudovanie/pripoj-pos