Soldering aluminum at home with a gas torch
Soldering aluminum at home can be considered a difficult task. But with the right approach and compliance with the appropriate technology, it is quite possible to perform it even for an inexperienced master.
Soldering aluminum at home
Problems often arise when using the wrong flux, for example when soldering steel or copper. It is very important to use a special substance for soldering aluminum, as well as suitable solder. If they are used, soldering aluminum will not cause any particular difficulties.
Features of aluminum soldering
Soldering aluminum at home can be accompanied by some difficulties that are associated with the special characteristics of this metal. In particular, with the fact that the surface of aluminum parts is covered with an oxide film.
It interferes with the process of making connections due to its high melting point, exceeding the properties of pure aluminum. Also, the oxide film is resistant to aggressive environments and active chemicals.
Because of this, the film prevents the connection of aluminum parts and solder.
To avoid such difficulties, it is worth cleaning the surface of products from film, which can be done using abrasive materials or using flux. Flux consists of potent substances that can destroy the oxide.
The melting point of aluminum, unlike oxide, is much lower, approximately 660 degrees, which often causes complications. When overheated, aluminum can significantly lose strength, become deformed, or become completely unusable.
Melting point of aluminum and its oxide film
The use of solders that contain such components should be avoided. They do not bond well with aluminum, which causes a poor-quality connection.
Zinc, which has good solubility, interacts best with aluminum.
Soldering methods at home
There are several methods of soldering, the most popular are methods using a soldering iron and soldering aluminum with a gas torch. There are three ways to solder parts:
- Soldering with rosin is used to join small aluminum parts, wires and cables. To do this, you need to clean the work area and cover it with rosin. Then press with a heated soldering iron several times. For these purposes, you need to use a rosin solution in diethyl ether.
Aluminum soldering process
Soldering is performed without removing it from the work area, followed by the addition of rosin. It is recommended to use a soldering iron with a power of 50 W. If the thickness of the parts and wire exceeds 1 mm, the power should be increased to 100 W, and it is better to warm up thicker objects in advance.
This method is most widely used in electrical work and soldering of automotive parts. Before performing work, parts must be tinned. This allows you to connect parts with other alloys and metals. In this case, aluminum is soldered with tin or solder containing zinc and cadmium. This allows connections to be made at temperatures of 400 degrees, which does not affect the physical properties of aluminum.
- Solder is necessary when using almost all soldering methods, whether using a soldering iron or a torch.
- The electrochemical method involves the creation of galvanic coating, which is performed using a special installation or manually. To do this, you need to apply a solution of copper sulfate to the cleaned surface. After this procedure, the parts are exposed to a negative electric pole.
Materials and tools
To perform aluminum soldering, you must have various materials and tools, which include heating tools, solders and fluxes.
Required materials and tools
An electric soldering iron is most often used as a heating tool. It can be considered a universal tool that is easy to use at home. But with its help you can only repair small items, usually small-diameter pipes, wires and cables, as well as small electrical appliances. It can be used at home in a ventilated area, as it does not require special conditions and a lot of space.
Large items should be soldered using a gas torch running on argon, propane or butane. At home, you can also use a blowtorch.
When using burners, it is necessary to strictly control the supply of flame, which should be characterized by maintaining the balance of gas and oxygen. When carrying out work, the flame should be bright blue. Any color changes may indicate too much oxygen.
Solders for soldering aluminum
Soldering aluminum is a very difficult task. Therefore, the choice of solder is important to create a high-quality seam and a strong connection. When using a conventional soldering iron, you need to select solder from a metal that has a low melting point. The most common alloys are:
- zinc-tin;
- bismuth-tin;
- copper-tin.
These types are often called amateur radio. They have a low melting point, which is very important for maintaining aluminum in its original state without changing the structure and physical properties. The cost of such solders is low, so their purchase becomes affordable for home craftsmen.
Solders for aluminum
But their use has a number of disadvantages and a limited scope of application. Thus, connecting objects using such solder is not highly durable and reliable. Therefore, they are used almost exclusively when repairing electrical equipment, including connecting wires and cables.
When repairing large aluminum objects using such solders, the connection will quickly lose strength and collapse. In such cases, it is better to use refractory solder, which contains zinc and tin.
But to create strong connections, refractory solders containing aluminum, copper and silicon should be used. Due to the presence of aluminum in the composition, the solder dissolves well in the structure of the repaired item.
It is impossible to use such solder when working with a soldering iron, since their melting point is about 600 degrees. Therefore, to work with them you need to have a gas burner.
It should be noted that when soldering using a gas torch, the metal of the workpiece does not melt; only the solder will melt.
Fluxes for aluminum soldering
When soldering aluminum, you need to use special fluxes, since not every flux is active towards aluminum. The most suitable substances are those based on ammonium fluoroborators and triethanolamine. Most special fluxes are marked with special markings, which indicate the possibility of their use when soldering aluminum.
Fluxes for aluminum soldering
If it is necessary to work at high temperatures, you should pay attention to mixtures containing potassium chloride, which makes up half; potassium chloride; sodium fluorite and zinc chloride. This composition allows you to create the most optimal conditions for high-temperature work.
Step-by-step instruction
Soldering technology depends on the method of performing the work. But the preparatory stage is almost identical in all cases. You should start working with the following operations:
- degreasing the surface of the workpiece using a solvent, such as gasoline or acetone;
- cleaning of the oxide film, which can be done using a wire brush, sandpaper or other abrasive material.
Then you should warm up the place where you are working. Depending on the size of the item, you can do this using a soldering iron or torch. In this case, you should follow several recommendations:
- It is not recommended to overheat the surface - this may lead to melting of the aluminum. Heating can be controlled using solder; if it begins to melt when it touches the workpiece, this means that the heating temperature is optimal and subsequent heating should be stopped.
- There is no need to use additional oxygen saturation, which can lead to a chemical reaction with aluminum and the creation of an oxide film.
Soldering work should be carried out depending on the type of heating object. When using a gas torch, you need to apply solder with flux to the work surface and then heat it.
It is very important to completely melt the solder, but not to overheat the workpiece. It’s easier to do this with a soldering iron, but in this case it’s difficult to complete a large amount of work.
By controlling the speed of movement of the solder and the temperature of exposure, you can create a seam of the desired thickness and structure. To improve the quality of work, it is recommended to pre-tinning the treatment area and treating it with an anti-corrosion agent.
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Source: https://rem-serv.com/payka-alyuminiya-v-domashnih-usloviyah-gazovoy-gorelkoy/
How to solder aluminum with a torch - Metals, equipment, instructions
Soldering aluminum, as many experts rightly believe, is a rather difficult technological process to perform.
Meanwhile, this opinion can be considered correct only in relation to those situations when they try to solder aluminum products using solders and fluxes that are used to join parts made of other metals: copper, steel, etc.
If you use a special flux for soldering aluminum, as well as the appropriate solder, then this technological process does not present any particular difficulties.
Soldering aluminum using a propane torch
The difficulties encountered in soldering aluminum using traditional solders and fluxes are explained by a number of factors, mainly related to the characteristics of the metal.
The main one of these factors is the presence of an oxide film on the surface of aluminum parts, which is characterized by a high melting point and exceptional chemical resistance.
When soldering, such a film prevents the connection of the base metal and the solder material.
Before soldering aluminum products, their surfaces must be thoroughly cleaned of the oxide film, for which you can use mechanical processing or use fluxes that contain potent components.
Duralumin parts prepared for soldering
This characteristic of aluminum leads to the fact that when heated, parts made from it quickly lose strength, and at a certain temperature, in the range of 250–300 degrees, structures made from this metal begin to lose stability.
The most fusible component, which is part of the most common aluminum alloys, begins to melt already in the temperature range of 500–640 degrees, which can lead to overheating and even melting of the parts themselves.
The basis of most low-melting solders used for soldering is tin, cadmium, bismuth and indium.
Aluminum does not bond well with these elements, which makes solder joints made using them very weak and unreliable.
Aluminum and zinc have good mutual solubility, so this element, when used in solders, provides the resulting joint with high strength.
Characteristics of fluxes for soft soldering
Composition of fluxes used for soldering aluminum
When soldering aluminum products, you can use solders of the tin-lead group if you thoroughly clean the surface of the parts and use highly active fluxes.
The compounds obtained with their help, due to the poor mutual solubility of aluminum, tin and lead, are characterized by low reliability, and they are also prone to the development of corrosion processes.
To make such compounds more resistant to corrosion, they must be coated with special compounds.
The highest quality, reliable and corrosion-resistant solder joint allows us to obtain solders containing zinc, copper, silicon and aluminum.
Solders containing these elements are produced by both domestic and foreign companies.
The zinc contained in the solder for soldering aluminum products determines not only the strength of the resulting joint, but also its corrosion resistance.
Tin-lead solders have the lowest melting point of all of the above. The highest temperatures are those that contain aluminum and silicon, as well as materials containing aluminum along with copper and silicon. The latter, in particular, includes the popular brand 34A solder, the melting point of which is in the range of 530–550 degrees.
For information: materials based on aluminum and silicon melt at a temperature of 590–600 degrees.
Taking into account the melting point, such solders are used in cases where it is necessary to connect large-sized aluminum parts that provide good heat dissipation, or products made of aluminum alloys that melt at fairly high temperatures.
But, of course, low-temperature solders demonstrate maximum ease of use, one of the most common brands of which is HTS-2000.
Solder HTS-200 for soldering parts made of aluminum and non-ferrous metals
The technology for soldering aluminum necessarily involves the use of a special flux, which is necessary in order to improve the adhesion of the base metal to the solder material. That is why it is necessary to approach the choice of such material very responsibly.
This requirement is especially relevant in cases where aluminum parts need to be soldered using tin-lead solder. The composition of fluxes contains elements that form its activity towards aluminum.
These elements include: triethanolamine, zinc fluoroborate, ammonium fluoroborate, etc.
Flux F-64 for soldering light alloys without preliminary mechanical surface treatment
Among the popular high-temperature fluxes, we should highlight the 34A material, which contains 50% potassium chloride, 32% lithium chloride, 10% sodium fluoride and 8% zinc chloride.
To obtain a high-quality and reliable connection, it is not enough just to know how to solder aluminum; it is also important to properly prepare the surfaces of the parts to be joined for soldering. This preparation consists of degreasing surfaces and removing the oxide film from them.
For degreasing, traditional means are used: acetone, gasoline or any suitable solvent.
Removing the oxide film before soldering, which is also easy to do with your own hands, is mainly done using mechanical processing, for which you can use a grinder, sandpaper, a metal brush or a stainless wire mesh. Much less commonly used is a chemical method for removing such a film, which involves etching the surface of aluminum parts using acid solutions.
Cleaning surfaces before soldering using a grinder attachment
As is known, an oxide film on the surface of aluminum forms almost instantly upon its contact with ambient air. This process also occurs on a surface that has been cleaned before soldering, but the point of cleaning is that the newly formed film is much thinner than the removed one, so it will be much easier for the flux to deal with it.
A gas burner running on propane or butane is predominantly used as an element used to heat the dimensional aluminum parts being connected and melt the solder. If you decide to solder aluminum products with your own hands in a home workshop, then you can use a regular blowtorch.
Easy to use gas blowtorch
When heating parts and solder before starting soldering, it is also necessary to monitor the flame of the gas burner: the mixture of gas and oxygen that forms it must be balanced.
This must be done for the reason that a balanced gas mixture actively heats the metal, but does not have a serious oxidizing effect. The fact that the gas mixture is balanced is indicated by the bright blue color of the flame, which is small in size.
If the burner flame is too small in size and has a pale blue color, then this is evidence that there is too much oxygen in the gas mixture.
For soldering small aluminum products, electric soldering irons and solders that melt at a low temperature are used.
Soldering techniques
Soldering parts made of aluminum, in terms of execution technology, is practically no different from the process of joining products made of other metals.
First, the parts to be joined are degreased and thoroughly cleaned, after which they are placed in the desired position relative to each other.
Then it is necessary to apply flux to the area of the future connection and begin heating it together with the solder to operating temperature.
Soldering process of aluminum alloy parts
When the operating temperature is reached, the tip of the solder will begin to melt, so they need to constantly touch the surface of the parts, controlling the heating process.
Soldering aluminum products, for which flux-free solder is used, has its own characteristics.
They consist in the fact that in order for the penetration of solder to the surface of the part not to be hampered by the oxide film, its tip must be made in striking movements at the site of the future connection.
In this way, the integrity of the film is disrupted, and the solder seamlessly connects to the base metal.
You can see how soldering is done practically in the training video.
There is another technological technique that allows you to destroy the oxide film during the soldering process. This can be done using a stainless steel rod or a metal brush, which is passed over the joint and the already molten solder.
To obtain the most durable connection using the soldering method, the surfaces to be joined must be pre-tinned.
Scope of the process
Not only soldering aluminum at home is of great practical importance. This technology is also actively used at repair and production enterprises. Using the soldering method, it is possible to obtain connections that are characterized by high strength, reliability and aesthetic appeal.
When working with thin sheet aluminum, soldering avoids deformation of the material
This technology is very popular when performing repair work on vehicles, tractors and motorcycles. This popularity is explained by the fact that when soldering there is no change in the structure of the metal being joined, therefore this method of connection in many cases is even more preferable than welding.
Home repaired car radiator
Burnouts, chips and cracks formed in a cylinder block made of aluminum alloy can also be successfully repaired by soldering. This technology is very useful if it is necessary to restore worn internal threads.
Source: https://spb-metalloobrabotka.com/kak-payat-alyuminiy-gorelkoy/
How to solder aluminum with a gas torch
The process of soldering aluminum is a very popular process, both at home and in industrial areas, since thanks to it it is possible to connect various small parts, but one also has to deal with larger parts. There are many types of metal welding, but sometimes soldering is used for a more suitable and high-quality connection.
In this regard, soldering aluminum with a gas torch is considered a very popular method, since there are several advantages that are not known to beginners.
Soldering aluminum is not very convenient, unlike other methods, however, it is still preferable to others, since at high temperatures the structure of the metal changes with the use of welding, so it is not used.
The essence
To carry out a quality process, it is necessary to use various auxiliary devices that are required by technology that has existed for a long time.
When soldering aluminum, significant difficulties arise with the oxide film on the metal surface, which forms almost immediately, and even after preparatory procedures.
Carrying out the soldering process using a torch is considered much more convenient than using a soldering iron, since there is the necessary temperature adjustment, thanks to which it becomes possible to more accurately process the surface of the metal, both thin and thick.
When soldering aluminum with a gas torch is carried out at home, preheating the metal, as well as melting additional consumables, is easier.
It is known that aluminum is one of the metals that melt easily, making working with them difficult, since the metal becomes highly fluid; a lot of experience is required to carry out a high-quality process. When the metal begins to spread over the surface, it will not be able to fill the seam, much less seal holes and cracks, so the necessary skills will be required.
There are many types of metal soldering, so the correct choice of filler material is important, and solders must be selected accordingly to the upcoming process.
Thanks to aluminum soldering, it is possible to connect both different mechanism housings, including thick sealed containers, and ordinary wires.
Soldering aluminum wires is quite easy using a torch, since there is the necessary adjustment of the flame temperature, as well as its intensity.
Advantages
- The process of soldering aluminum using a gas torch is considered universal compared to using a soldering iron, since it is possible to connect both thin and thick different parts;
- Thanks to a gas burner, it is possible to carry out the necessary regulation of the intensity of the flame, thanks to which you can determine the temperature, while when using a soldering iron, you will need to have some devices of various powers available;
- A gas burner can provide the necessary heating of the surface of the material, melting the solder and flux;
- The process of soldering with a gas torch takes a correspondingly long time, so it becomes possible to form a better-quality connection;
- After completing the process, the connection result will be much better than using a soldering iron;
- With such a device, you can almost immediately carry out new work without waiting for the tool to cool down.
Flaws
- Preparatory work takes a very long time;
- Prices for performing such work are very expensive, unlike other methods;
- Such a process is very unsafe, since due to the container in which the gas is present, an explosion can occur when exposed to an open source of flame, and cracks can also form in the hoses over time, which has a negative effect on the respiratory system;
- The cost of equipment for work is very expensive.
Materials and accessories
- The main device for soldering is a gas burner; gas flows through it under pressure. During the soldering process, it exerts a temperature effect, due to which the solder metal melts, and it is also possible to heat the material. By adjusting the pressure supply as necessary, the flame temperature can be determined;
- A gas cylinder, the size of which may not necessarily be standard. The cylinder contains consumable flammable material, so it must be isolated at a safe distance from flames;
- The hose that goes from the cylinder to the burner. Before starting the process, it is recommended that they always pay attention, checking their connections, as well as the integrity of themselves;
- Solder for soldering aluminum, which may vary depending on the upcoming procedures. Before soldering with a gas torch, filler wire is also required depending on the base material;
- Flux, which improves the soldering process. This substance is mainly used for joining thick workpieces, but is also used for soldering various types of metal, such as aluminum, or in particularly difficult cases.
Torch soldering modes
| Workpiece thickness, mm | Solder consumption, g | Gas consumption, ml |
| 1-2 | 0,5-1 | 3-5 |
| 2 -4 | 1-1,5 | 5,5 |
| 6 | 1,5 | 7 |
| 10 | 2 | 11 |
Safety precautions
At the beginning of each use of the equipment, it is necessary to check the integrity and serviceability of the gas cylinder and hoses.
The cylinders will need to be placed at the required distance of at least 5 meters from such work and the source of flame.
It is not recommended to leave various flammable objects or flammable substances near the cylinder.
Source: https://strinstrumenty.com/alyuminij/kak-payat-alyuminij-gazovoj-gorelkoj.html
Soldering aluminum with a gas torch
The process of soldering aluminum is a very popular process, both at home and in industrial areas, since thanks to it it is possible to connect various small parts, but one also has to deal with larger parts. There are many types of metal welding, but sometimes soldering is used for a more suitable and high-quality connection.
In this regard, soldering aluminum with a gas torch is considered a very popular method, since there are several advantages that are not known to beginners. Soldering aluminum is not very convenient, unlike other methods, however, it is still preferable to others, since at high temperatures the structure of the metal changes with the use of welding, so it is not used.
How to solder aluminum with a torch - Metalworker's Guide
The process of soldering aluminum is a very popular process, both at home and in industrial areas, since thanks to it it is possible to connect various small parts, but one also has to deal with larger parts. There are many types of metal welding, but sometimes soldering is used for a more suitable and high-quality connection.
In this regard, soldering aluminum with a gas torch is considered a very popular method, since there are several advantages that are not known to beginners. Soldering aluminum is not very convenient, unlike other methods, however, it is still preferable to others, since at high temperatures the structure of the metal changes with the use of welding, so it is not used.
Soldering aluminum at home
Soldering aluminum at home can be considered a difficult task. But with the right approach and compliance with the appropriate technology, it is quite possible to perform it even for an inexperienced master.
Soldering aluminum at home
Problems often arise when using the wrong flux, for example when soldering steel or copper. It is very important to use a special substance for soldering aluminum, as well as suitable solder. If they are used, soldering aluminum will not cause any particular difficulties.
Methods for soldering aluminum wires
Despite the fact that in modern construction, during electrical work, aluminum cables are increasingly being replaced by copper cables, aluminum remains an indispensable material in the manufacture of large-section wires and cables.
The reasons for this lie on the surface - the electrical resistivity of aluminum is approximately one and a half times greater than that of copper, and the volumetric weight is three times less.
With a large conductor cross-section, when weight is more important than strength, the choice in favor of aluminum is obvious. The cross-sectional area of an aluminum conductor will be one and a half times greater than that of a copper conductor, and at the same time, aluminum will still be two times lighter than copper. Soldering, among other methods, is used to connect wires.
Soldering methods
The problem with using aluminum conductors is their rapid oxidation. The oxide film significantly impedes the passage of electric current during connections. To do this, twisted aluminum wires are soldered.
You can solder aluminum wires in a junction box using a soldering iron or a gas torch. It is more difficult to use a soldering iron due to the inability to accurately heat to the required temperature. And for aluminum, overheating is just as unacceptable as underheating.
Metal has high thermal conductivity, and the insulation over a large area from the soldering point can simply melt.
It is easier to regulate the heating temperature with a gas burner, but it takes a long time to prepare the surface. However, it is the torch that will need to be used if it is necessary to solder any massive parts to each other. In any case, when soldering aluminum wires, they need to be prepared.
Preliminary processing
The difficulty with soldering is that aluminum itself is a very low-melting material (660 ℃) and if heated carelessly it can melt.
Another factor that makes soldering aluminum wires difficult is rapid oxidation in air.
The oxide film on the surface of the material reliably protects aluminum from the effects of all kinds of external factors, but it also prevents the adhesion of solder to the material and must be removed.
It is almost impossible to mechanically remove the oxide film under normal conditions. The material is instantly oxidized and covered with a new film. You can mechanically remove the oxide film under the oil layer.
But before this, the oil must be heated to 200 ℃ in order to remove any active oxygen that may be present there. This method is very inconvenient at home and labor-intensive.
Therefore, the ends of aluminum conductors must be tinned before soldering. Using rosin or most other fluxes will not work due to the high chemical resistance of the oxide film. It does not dissolve even with organic acids.
To tin the wires, you must use both a special flux and a mechanical method.
Of course, this must be done before the wires are twisted, otherwise it will not be possible to mechanically clean the entire surface of the wire. Only the tinned ends can be twisted together and soldered.
Working with a soldering iron
In order to solder aluminum with a soldering iron, there are several methods, the essence of which is to clean immediately under the flux layer in direct contact with the molten solder.
The first method is that aluminum conductors, before soldering, are cleaned with a hot tinned soldering iron using a mixture of rosin and steel filings.
Sawdust has an abrasive effect, rosin removes all impurities and immediately the cleaned areas are covered with solder, which should be on the soldering iron tip.
The second method involves stripping the aluminum wire on medium-grit sandpaper directly under the influence of a hot soldering iron with solder and flux.
Gas burner
Processing with a gas burner is carried out when the parts are in the position relative to each other in which they will be used. The processing smoothly transitions into the soldering process itself.
This happens as follows:
- the burner heats the surfaces of aluminum parts;
- upon reaching the temperature at which the metal is reduced from the oxide, the film is mechanically peeled off;
- under the influence of a flame, the parts are coated with flux, and solder is introduced into the soldering area.
If the parts are thick, then their edges must be cut at an angle of 45°. Typically, heating occurs to the melting point of tin, when the solder spreads and fills the twist groove.
Differences in technology when using flux
Thanks to the achievements of modern science and technology, flux compositions for aluminum have been obtained that actively dissolve the oxide film and protect the material from further oxidation.
Examples of such drugs are formulations labeled F-59A and F-61A. The letter A means that these compounds are intended for soldering aluminum.
When using these fluxes, soldering aluminum wires is greatly facilitated. It is enough to simply treat the finished twist with flux, without even heating it, and then, after heating it with a soldering iron or torch, apply solder.
It will spread over the entire surface of the wires and adhere well, providing a strong and electrically conductive solder joint.
Features of soldering stranded wires
Stranded wires must be soldered only using a special flux, since their mechanical processing is almost impossible. Soldering technology differs in that each wire must first be well treated with flux.
To do this, the bundle will have to be untwisted and fluffed. After processing, each thin wire conductor is covered with solder and the bundle is twisted. After this, twist the two ends and solder it.
Can it be connected to copper?
Situations often arise when it is necessary to connect an aluminum wire to a copper wire. This is perhaps the only case where soldering cannot be used.
It's all about the aluminum itself. It cannot be soldered to other metals at all due to its physical and chemical properties. When connecting directly to copper, galvanic corrosion will occur between the two active metals and will quickly destroy the connection.
And if they are soldered using solder that is neutral to both materials, then the different coefficients of thermal expansion of the metals will quickly destroy the soldered contact. After all, when current passes through a conductor, it will certainly heat up, and after switching off, it will cool down.
Difficulties in soldering aluminum wires
The main difficulty when soldering aluminum wires, as indicated above, is the presence of an oxide film on the surface of the metal. Fighting it greatly slows down the soldering process.
And if you consider that aluminum wires are now used mainly for laying external power wiring, it becomes obvious that a regular soldering iron and sandpaper will not be enough in this case. Welding is increasingly being used to connect such wires.
Source: https://svaring.com/soldering/praktika/pajka-aljuminievyh-provodov
Soldering aluminum at home with a soldering iron or gas torch - Website about
Hi all! Many people know that aluminum is soldered mainly in an argon atmosphere with a special welding machine, but there is also an option for working with a gas torch, and even a turbo lighter can be used on a small scale.
In general, this is not my first acquaintance with this wire, but the shopping experience is not very good, so I will share not only the test result, but also trusted places to buy so as not to get sample No. 2 , but let’s start in order.
- Characteristics
- Unboxing and appearance
- Testing
- Results
Characteristics
Diameter: 2.0 mm Length: 500 mm Soft solder ISO 3677: ~B-Zn98Al 381-400 Approximate composition (weight%): 2.4 Al – rest Zn Melting point ºС: 360 Tensile strength (MPa): Up to 100 (Al) Density (g/cm3): 7.0
Unboxing and appearance
The last and most profitable purchase was sample No. 3 from banggood.
Came in a small gray package
The rod is additionally packaged in a transparent zip bag.
5 meters cost me $8 with points, that is $1.6 per meter - go to the store
White powdery flux is visible in the center, the rod is moderately hard, looks like aluminum without oxidation
Comparison
The first one I bought was the leftmost sample No. 1 from Ali. Its properties are absolutely identical to sample No. 3 , but 3 meters cost me $12 , that is, $4 per meter , which is almost three times more expensive. check current price
In the center is sample No. 2 . It costs $5 for 3 meters or $1.7 per meter , like sample No. 3
But as soon as you take the bag in your hand, you realize that this is a POS with not very thick flux inside.
don't buy here
Two more samples at $8 for 3 meters were never delivered, they were probably not even sent.
Testing
Over time, aluminum becomes covered with an oxide film, due to which the surface becomes dull, so, before soldering, the surfaces must be cleaned to a shine, otherwise the solder will simply roll off in balls on the surface, regardless of the degree of its heating. Sample No. 1
In general, it is correct to heat the part to a temperature of about 400 degrees, and then simply move the rod, which will melt and fill the cracks, but I have little experience, so in order not to overheat the surface, I periodically bring the rod into the burner flame. If the temperature is low, the solder will roll down the surface like a ball; if it is sufficiently high, it will tin it.
The fracture test shows a good result - the break does not occur along the seam
Sample No. 2 . It melts very well, emits a lot of smoke, and smells like burnt “aspirin.” It sticks to aluminum, but if you overheat it, it burns out pretty quickly.
- It is inconvenient to work due to the stench and the need to control the temperature.
- Sample No. 3 . I decided to solder the tubes with the outer walls
- We try to break the seam. After the tube came out of the vice, I clamped it higher, bringing it out of focus and only noticed this at the stage of creating GIFs
- But there is a photo of the result which shows that the seam was not damaged.
And finally, let’s splice the aluminum tube with a piece of duralumin.
The tear test was also successful.
Results
An interesting wire - aluminum solders perfectly, filling even small gaps, the main thing is that the joints are not dirty. It also sticks well to copper, but experienced people say that it is better to use other alloys to work with it, although this rod is quite suitable for emergency field repairs.
The melting point of aluminum is about 660ºC, it would seem that you can use rods at 450-500 degrees, but you may encounter two problems: 1. A massive part needs to be heated up to 500 degrees with something else 2. You can overheat the soldering area and ruin the part
Sample No. 3 seemed to me the most optimal . It corresponds to the declared characteristics and costs at least half as much as the others. There are also lots of different lengths to choose from: 1 meter - $2.89 2 meters - $4.39 3 meters - $6.39 5 meters - $9.89
go to the store
Source: https://nzmetallspb.ru/tehnologii/pajka-alyuminiya-v-domashnih-usloviyah-payalnikom-gazovoj-gorelkoj.html
