Instructions for welding aluminum with argon for beginners
The most effective way to create a permanent connection of parts made of aluminum and alloys based on this metal, as practice shows, is welding aluminum with argon.
Any welding technology that involves the use of shielding gas requires the use of special equipment, as well as the welder having the appropriate knowledge, qualifications and experience in performing such work.
In addition, it is necessary to have at least basic knowledge in the field of metallurgy in order to understand what processes take place in the weld pool.
Aluminum argon arc welding process
What properties of aluminum should be taken into account when welding it?
Understanding the nuances of the processes occurring in the structure of aluminum when performing welding work with it is especially important for novice welders. To understand this well, you need to become familiar with the chemical properties of this metal, which is characterized by its low specific gravity, high strength and exceptional chemical reactivity.
The most significant characteristic of aluminum, which not only experienced but also novice welders should know about, is its ability to quickly react with oxygen, which leads to the formation of a refractory oxide film on the surface of the metal.
Typically, aluminum itself can melt at a temperature of 650 degrees, and to melt the oxide film covering its surface, a heating temperature exceeding 2000 degrees is required.
When welding with direct current, the unmelted oxide film can be immersed in the molten metal, thereby deteriorating its internal structure.
Argon arc welding diagram
Another feature that should be taken into account when welding this metal is that it does not change its color when heated. Because of this, it is quite difficult to visually determine the degree of heating of the parts being joined, which often leads to burn-throughs and leakage of molten metal during welding.
A property of aluminum that should be taken into account if you are planning to weld parts from this metal is a significant coefficient of its volumetric shrinkage, which often leads to the occurrence of stresses and deformations inside the formed weld and, as a result, to the formation of cracks in it. To avoid such unpleasant consequences, it is necessary to modify the weld or compensate for metal shrinkage by using more welding wire.
Any instruction for welding aluminum, as well as alloys based on it, requires that the specialist performing it is aware of the characteristics of this metal, which include:
- high chemical activity;
- low melting point of the metal itself;
- significant volumetric shrinkage.
Considering all of the above, it can be argued that it is thanks to welding aluminum with argon that high-quality, beautiful and reliable connections of parts are obtained. And if you use semi-automatic equipment to perform such welding, you can effectively solve two problems at once: protect the welding zone from harmful environmental influences, and also compensate for significant metal shrinkage due to the constantly supplied welding wire.
Of course, in addition to this technology, there are other methods of joining aluminum parts using welding, the specifics of which every specialist should know about.
Modes of argon arc welding of aluminum and its alloys
Aluminum welding methods
In addition to welding, which involves the use of argon as a shielding gas, aluminum parts can be welded using other technologies. The most common are:
The first of the above aluminum welding technologies involves the use of filler wire fed into the welding zone, as well as a special flux consisting of fluoride and chloride salts.
The flux, which together with the filler rod is heated by the flame of a gas burner, corrodes the oxide film and opens the flame to the base metal, which melts at a fairly low temperature.
After completing welding work performed using this technology, it is necessary to immediately wash the surfaces of the parts to be joined in order to wash off any remaining caustic flux from them. The great advantage of this technology is that its use ensures minimal consumption of filler material.
Equipment for semi-automatic welding in argon
To connect aluminum parts, an electric arc welding machine, special aluminum electrodes or filler wire coated with flux can also be used. Welding when using such a device is performed with direct current connected with reverse polarity.
However, as noted above, the highest quality connection can be obtained by argon arc welding of aluminum. When using this technology, heating of the parts to be joined is ensured by an electric arc burning between an infusible tungsten electrode and the workpieces being joined. The formation of a weld occurs through the use of aluminum wire fed into the arc combustion zone manually or mechanically - in semi-automatic welding.
Equipment for manual argon arc welding
The high temperature created when an electric arc burns makes it possible to destroy the oxide film on the surface of the parts being joined, and so that the aluminum does not have time to go into the liquid phase and leak out of the zone of the joint being formed, the welding electrode is moved at a fairly high speed. The big advantage of this welding method is that the electrode, made of refractory tungsten, lasts for a long time, and this allows you to save on consumables.
In order for a weld made semi-automatically using filler wire to have high quality and reliability, it is necessary that the chemical composition of such wire matches the composition of the workpieces being joined to the maximum extent possible.
To perform welding using this technology, today we use devices that generate direct or pulsed current, and there are also devices that use alternating current to weld.
Argon welding technology
Welding with argon, which falls under the definition of welding in a shielding gas environment, requires strict adherence to the instructions, which stipulate the sequence of actions performed by a specialist.
Both the quality of the formed connection and the consumption of materials, which are not cheap, depend on how correctly all these actions are performed.
If you have never performed such welding work, then you need to not only study step-by-step instructions, but also carefully watch video lessons that detail the entire technological process.
To weld aluminum and alloys based on this metal in an argon environment, you need not only the welding machine itself, but also additional equipment that provides storage and supply of consumables. Naturally, the technical condition of such equipment and the quality of all materials used directly affect the reliability of the connection being formed.
To perform argon welding of parts made of aluminum and alloys based on this metal, you will need the following equipment:
- a source of electric current to which the welding machine and all other equipment will be connected;
- a cylinder in which the protective gas argon is stored;
- a mechanism responsible for feeding filler wire into the welding zone.
When welding with argon at large industrial enterprises, shielding gas is supplied to the welding machine through a centralized network. The welding wire used in semi-automatic machines is pre-wound on special reels installed on such a machine. The working surfaces of workbenches on which welding operations are performed, according to the instructions, must be made of stainless steel.
How to prepare parts to be joined for welding
The quality of aluminum argon welding is influenced not only by the technical condition of the semi-automatic machines and other devices used, but also by the thorough preparation of the workpieces being joined.
The step-by-step video below demonstrates all the stages of such preparation well:
To obtain a high-quality connection, it is necessary to thoroughly clean the parts being connected from dirt, grease and traces of machine oil. For such cleaning, it is best to use any solvent.
If the thickness of the joined sheet blanks exceeds 4 mm, it is necessary to cut the edges, and the aluminum welding itself must be performed only butt-to-butt.
To remove the refractory oxide film from the surface of the workpieces, the joint must be processed using a file or a brush with metal bristles. If the joint has a complex configuration, then such cleaning can be done using a grinding machine.
Some features of argon welding
Welding performed in an argon environment has some technological features that a training video cannot always explain. As mentioned above, for such welding, performed semi-automatically or with manual supply of additive, tungsten electrodes are used, the diameter of which is selected in the range of 1.5–5.5 mm.
Such an electrode, which forms the welding arc, is located at an angle of 80 degrees to the surface of the parts being connected. If the filler wire is supplied not semi-automatically, but manually, then it is positioned at an angle of 90 degrees relative to the electrode.
If you carefully watch the video of aluminum welding with argon, you will notice that the filler wire moves in front of the electrode.
Modes for welding aluminum with a tungsten electrode
When welding with argon, it is very important to ensure that the arc length is within 3 mm. A characteristic feature of such welding is that when it is performed, the filler wire does not make transverse movements.
Argon welding, if it is used to connect sheets of aluminum of small thickness, is performed with a backing, which can be used as a sheet of stainless steel. This allows for improved heat removal from the welding zone, avoiding burns and leakage of molten metal. The use of a backing, among other things, saves energy, since such welding in an argon environment can be performed at a higher speed.
Pros and cons of welding performed in argon
Argon welding of parts made of aluminum and alloys of this metal has a number of significant advantages when compared with other technologies.
When using this method, the parts being joined heat up very little, which is especially important in cases where it is necessary to weld workpieces of complex configurations.
The connection obtained by welding in an argon environment is characterized by high strength and uniformity of the weld, which is free of pores, impurities and foreign inclusions. It is very important that the seam obtained by welding with argon is characterized by a uniform penetration depth along its entire length.
Scheme of argon welding using a non-consumable tungsten electrode
Naturally, welding aluminum with argon has disadvantages that you should also be aware of. The main one of these disadvantages is the use of complex equipment. To ensure high efficiency of welding operations and the required quality of the weld, it is necessary that the welding machine itself and all additional equipment are configured correctly.
One of the most important parameters that should be correctly adjusted when welding in argon and other shielding gases is the speed and uniformity of the filler wire feed. If the feeder is not configured correctly, the wire will flow into the welding zone intermittently, the welding arc will be interrupted, which will ultimately lead to increased consumption of electricity and argon.
Argon welding is a rather complicated process, but if you follow all the instructions and have the appropriate qualifications, it will allow you to achieve a good result.
Source: http://met-all.org/obrabotka/svarka/svarka-alyuminiya-argonom-poshagovaya-instruktsiya.html
Is it possible to weld aluminum with argon yourself?
If you need to connect aluminum workpieces, you should take into account the features of this alloy. The difficulty of welding aluminum workpieces lies in the appearance of an oxide film, which interferes with the creation of a reliable weld. Welding aluminum with argon allows you to create a good seam.
What needs to be taken into account when carrying out work?
Argon welding is used to join many homogeneous metals and alloys. The principle of operation of this equipment is the formation of an electric arc between a tungsten electrode and a metal surface, which allows the creation of a welding seam. A flow of inert gas is supplied to the surface being treated.
When carrying out work, a number of features should be taken into account:
- Formation of an oxide film. The film can be melted at a temperature of 2000 degrees Celsius. At the same time, aluminum melts at 500 degrees. To make a high-quality seam, you must first clean the workpiece from the oxide film. This can be done with a brush or solvent.
- Hygroscopicity. Aluminum actively absorbs moisture from the environment. When the workpiece is heated using a welding arc, the material begins to release accumulated moisture. To ensure a better quality weld, welders recommend preheating the workpiece to 150 degrees.
- Cleaning the treated surface from air. To do this, you need to set the correct argon flow. If there is not enough gas, the material will foam. The tungsten rod will be damaged. When too much gas comes in, it will prevent the seam from forming. Increased consumption will make the process of joining workpieces more expensive.
When welding with argon, difficulties arise in forming a seam. Beginners often end up with a recess (crankcase). This is due to prolonged heating of the surface. To avoid this problem, you need to set the arc attenuation mode correctly. With a uniform decrease in temperature, you can achieve a high-quality seam without the formation of a crater.
Aluminum welding methods
If it is not possible to use argon to protect the surface being welded from the formation of an oxide film, you can use other welding technologies:
- argon arc;
- electric arc;
- using a gas burner.
The third option for joining aluminum workpieces involves the use of flux and filler wire. Consumables are gradually transferred to the work area. When heated, the wire melts and connects the workpieces to each other. At this time, the flux heats up and protects the surface from the formation of an oxide film. When the work is completed, you need to clean the parts from flux.
Electric arc welding involves the use of aluminum electrodes and direct current with reverse polarity. Filler wire can be used instead of electrodes. A layer of flux is applied to the surface of the consumable.
The best option is to weld parts using argon. This uses tungsten electrodes for aluminum. An arc is formed between them and the surface being processed, which connects the parts.
Tig welding of aluminum
Advantages and disadvantages
Argon welding of aluminum has a number of strengths and weaknesses.
Advantages:
- High-quality connection of parts.
- Surface protection with gas.
- No deformation of processed parts.
- A universal technology that is suitable for joining various alloys and homogeneous metals. Suitable for using materials with high thermal conductivity.
- Productivity increase.
Flaws:
- Purchase of complex equipment.
- Experience in welding work.
Equipment
Before starting work, you should prepare the necessary equipment for welding. Features of consumables and devices:
- Electrodes that have a tungsten base. These are non-consumable elements to which alloying additives are added.
- A device that produces welding current. It is advisable to choose universal equipment that is suitable for performing a variety of welding jobs.
- Shielding gas cylinder. In this regard, it is most effective to use argon.
Special hoses and wires are used to connect the equipment.
Technology
The technology of welding aluminum with argon requires compliance with a certain sequence of actions. If you deviate from the specified workflow, connections may result in poor quality. Welders distinguish 4 key stages of argon welding.
Preparation
Before turning on the equipment, ignite the arc, the work surface should be prepared. To do this, you need to clean it from dirt, rust, and decorative coating. Coarse layers are cleaned off with a grinder or sandpaper. The surface is degreased with a solvent. The oxide film can be removed with a file.
How to set up the equipment?
Before starting work, you need to set up the machine for welding aluminum. First you need to connect the device to a protective gas cylinder. Next, the welder sets the argon supply. For this, a valve and a pressure gauge attached to the cylinder are used. If work is carried out indoors, the flow rate is set to 8 liters.
Arson arc
To make the arc ignite faster, the tungsten rod should be sharpened. A high-frequency oscillator is used to ignite it. Do not touch the tungsten electrode to the workpiece. If filler wire is used, it should not come into contact with the tungsten. Work should begin after the arc is ignited and the shielding gas flow is set.
Weld pool
After the arc has been lit, you cannot immediately begin to create a seam. You need to wait a certain period of time during which a weld pool is formed. When spots of molten metal appear, the formation of the seam can begin. The metal must not be overheated. It is important to consider the thickness of the workpiece.
The lower this indicator, the less time you need to wait when forming the weld pool.
Welding aluminum with argon involves the use of a specific apparatus and gas. It helps protect the work surface from the formation of an oxide film. If it is not removed, the quality of the seam will be worse. Under severe loads, the connection will collapse.
It is important to take into account the peculiarities of welding the alloy and follow the sequence of actions.
Source: https://metalloy.ru/obrabotka/svarka/alyuminiya-argonom
How to properly weld aluminum with argon: welding features and materials for work, instructions and recommendations
To reliably fix two or more aluminum-based elements to each other, it is best to use argon welding. To perform welding work in any inert gas environment, you will need special equipment and accessories.
And for beginners in this area, it is very important to study in detail how to cook aluminum with argon, since the special apparatus for connecting such parts is quite complex in its structure.
If you connect them using a semi-automatic device, you need to have a special welding wire and an argon cylinder. The welder must know the basics of working with metals and be qualified. If you are just learning, it is better to watch the training video and study the instructions.
Properties of aluminum
Any novice welder should know not only about the features of the argon welding process for aluminum, but also understand what properties this material has.
Many people call aluminum a “winged” metal because of its low specific gravity and strength. At the same time, it has high chemical activity .
Among the features of the metal:
- It has the ability to quickly enter into an oxygen reaction in open space and become covered with an oxide film.
- The film has a melting point of more than 2000 degrees, aluminum - from 650 degrees, respectively.
- During DC welding, oxide can sink into the weld metal and damage its structure.
- Aluminum does not change color when heated, like stainless steel or other types of steel.
- Aluminum has a high volumetric shrinkage coefficient. If this property is not taken into account, then tension will appear inside the seam and deformation will occur. To prevent this from happening, you should increase the amount of welding wire used or modify the seam.
The key properties of the metal are:
- low melting temperature;
- high chemical activity;
- large volumetric shrinkage coefficient.
Welding aluminum using argon is the most common , especially taking into account the listed features. This method is able to protect the welding zone from the influence of active gases that are in the atmosphere.
When welding semi-automatically, the filler wire performs the function of reducing internal weld stresses, because it compensates for volumetric shrinkage. A high-quality welded connection is also ensured by other methods.
Materials for work
The welding apparatus consists of the following parts: an argon cylinder; power supply; filler wire feeding mechanism. This wire comes on spools or spools.
At large production enterprises, such devices are connected to a centralized main line , through which inert gas flows. Workbenches for mounting welded parts are made on the basis of stainless steel.
Preparing parts
Once you have your aluminum welding equipment up and running, you will need to prepare the parts for welding. This is done like this:
- Remove grease, dirt or machine oil from their surface using a solvent.
- If the thickness of the parts is 4 mm or more, you need to cut the edges.
- According to technical specifications and expert recommendations, aluminum sheets with a thickness of 4 mm or more must be butt welded exclusively. Before starting work, you always need to clarify parameters such as sheet thickness and edge width in millimeters.
- Sand the edge using an emery machine or file. If the part has a complex shape, then the welding site must be cleaned with a mobile grinder. One way or another, the oxide film must be removed from the surface.
Key description of the welding process
In order for the work to be done efficiently, it is necessary, as mentioned earlier, to use tungsten electrodes. Their diameter should be 1.5−5.5 mm.
During the process, be sure to monitor the orientation of the electrode relative to the working surface of the metal. Hold the electrode at an 80 degree angle. And the filler wire must be kept at a right angle in relation to the electrode.
The maximum arc length is 3 mm. In this position, the consumption of materials will be most optimal. During operation, the filler wire will move ahead of the torch. It and the tungsten electrode must move exclusively along the welding seam . Transverse movements should not be allowed.
If you are working with thin aluminum sheets, then a stainless steel sheet is . In this position, intensive heat removal from the workplace through a stainless steel sheet is performed, and the risk of burn-through will be reduced. Energy consumption will also be reduced, because the work will be done quickly.
Pros and cons of argon welding
The method of joining aluminum parts semi-automatically in an argon environment has significant advantages over others.
First of all, it is worth mentioning the minimum heating area of the workpiece, which is important when welding parts that have a three-dimensional structure.
You can easily calculate the amount of gas required and find out what wire will be needed and in what quantity. But it is difficult to predict the internal deformation of the product.
Connecting parts in an inert gas environment will allow you to weld without impurities, pores and other unnecessary inclusions . The weld has the same penetration depth along its entire length.
The disadvantage of this welding is that the equipment is quite complex . During operation, it is necessary to fine-tune all components of the apparatus, and it is important that the wire is fed into the working area gradually. For this purpose, you need to configure the feeder in the correct way. If the feed is irregular, the arc will be interrupted. In this case, the consumption of argon and electricity will increase.
Connecting aluminum parts with argon is one of the common techniques. However, before you start working, you need to carefully study theory and practice , as well as watch a training video that can be easily found on the Internet.
Source: https://tokar.guru/svarka/svarka-alyuminiya-argonom-dlya-nachinayuschih-poshagovaya-instrukciya.html
Welding aluminum with argon for beginners - step-by-step instructions
/ Welding /
Do you want to conquer aluminum - this capricious, lightweight material with high electrical conductivity? Friends, it is possible!
Let's look at how to weld aluminum with argon for beginners; every beginner will learn step-by-step instructions with photos and videos.
Applications of TIG aluminum welding
The properties of aluminum and its alloys allow them to be used in almost all industries:
- food (tanks, pipelines, etc.);
- aviation (light and durable, it is also called volatile material);
- automotive (cylinder heads, propellers, etc.)
Healthy! To make the weld seam beautiful and of high quality, tig welding of aluminum with argon is used.
This method is also used when welding joints under ultrasonic and radiographic control.
It is impossible to master the method without understanding the characteristics of the material during welding.
: DIY welding inverter assembly diagram
Practice of welding aluminum with argon
The TIG/TIG process using argon and an inverter as a source to create the required thermal power requires known skill. Among them it is worth noting the following:
- The density of argon is much higher than the density of air, so vertical connection of aluminum structures in this way is impossible. If absolutely necessary, some helium is added to the argon cylinder.
- The movement of the welding torch should be carried out exclusively along the axis of the weld and perpendicular to it.
- Ignition and subsequent combustion of the welding arc must be performed at a minimum voltage, which will ensure stability of the process. Thus, the distance from the electrode to the joint surface is chosen to be the smallest.
- The tungsten wire must be fed evenly. In the absence of the necessary skills, special devices for automatic feeding are used.
- The processing current is set to the maximum possible (not lower than 250 A), which ensures the proper welding speed while keeping the PV within the limits acceptable for this inverter model.
It is recommended to weld aluminum structures using shielding gas in the following sequence. First, a cylinder with argon (or a mixture of argon and helium) is connected to the device. The gas pressure set by the reducer depends on where the welding is being done (indoors or outdoors), as well as on the thickness of the workpieces being joined. Indoors, a gas flow rate of 6-8 l/min is sufficient; for outdoor work, the flow rate will have to be increased to 8-12 l/min.
The initial metal surfaces are prepared - mechanically and chemically cleaned, and then heated to 250-3000C (the latter is especially important when working in unheated rooms or at low outside temperatures). The thicker the metal, the higher the heating temperature. Rapid cooling of thin-sheet structures is unacceptable, since the risk of warping increases. Electrodes are also subject to cleaning and drying at 150-2000C.
Aluminum is purified in an aqueous alkali solution consisting of the following components (calculation is made per liter of cleaning solution):
- Soda ash, g - 50;
- Trilon B (sodium salt of ethylenediaminetetraacetic acid EDTA), g - 50;
- Liquid glass, g - 30.
The solution is heated to 65±50C, and the prepared edges of the joints of aluminum parts are kept in it for at least 5 minutes.
The choice of tungsten wire diameter is determined by the thickness of the products being welded. It is believed that per 1 mm of electrode diameter it is permissible to introduce no more than 35-40 A of current. The end of the electrode is sharpened sharply, during the welding process it should take the shape of a hemisphere.
The protrusion of the electrode from the welding torch nozzle is set to a minimum - no more than 1-2 mm.
The starting current for stable arc burning when welding aluminum under argon is usually taken to be one and a half to two times greater than the values recommended by the manufacturer of the welding inverter, then it can be reduced to the established values.
The supply of tungsten wire begins only after a stable arc has been ensured. Long welds are produced using a four-stroke processing mode, and towards the end of the weld the current is gradually reduced.
Using aluminum argon arc welding requires certain skills, as well as experience in operating a welding inverter.
Process Features
Aluminum has properties that are not inherent in other metals. It is corrosion resistant, lightweight and very durable. Professionals assure that aluminum is one of the most difficult metals to weld. To carry out effective work, you need to know the features of this material.
Before you start gas welding aluminum, you need to understand what to expect. How to work, where to start and how to finish. For example, when heated, aluminum does not change color, unlike other materials.
When working with aluminum, the welder must know:
- Aluminum has an oxide film. This metal has a natural coating of an oxide film over its entire area. It serves as protection against the influence of external factors. It is worth understanding that this material has a melting point of 2050°C - higher than the boiling point of aluminum. Such a layer greatly complicates working with the metal itself, because it requires significant preliminary preparation. The top layer is removed mechanically or chemically. This must be done immediately before starting work, as the layer is self-healing. Aluminum has high chemical activity, and upon contact with oxygen after stripping, it quickly restores the upper oxide layer. Therefore, welding aluminum without argon will spoil the quality of the metal.
- Preparing aluminum for argon welding. Surface preparation is the main point when working with aluminum. Demanding metal requires pre-treatment. Regardless of the chosen method, you should immediately begin welding, or prevent oxygen from reaching the metal surface by wrapping it in plastic film. A correctly carried out preliminary preparation procedure will significantly simplify and speed up further welding. Just before you begin, go over the material again with a rough wire brush to complete the preparation.
- High temperatures are not required. Since aluminum conducts heat well, it heats up quickly and does not require high temperatures during operation. Here you should work with extreme caution, because it is very easy to burn through aluminum. Such damage is difficult to correct, and serious mistakes are irreparable.
- High power consumption. The thermal conductivity of aluminum is several orders of magnitude higher than that of metals of similar popularity. Compared to steel, this figure is 5-6 times higher, depending on the impurities in the alloy. Based on this feature, welding requires constant input of powerful heat. This is realized due to the power of the welding arc. But if you plan to weld a massive product or thick sheets, you should use preheating.
- Crater filling. Due to the property of aluminum to harden quickly, during welding in most cases a crater is formed, which must be welded at the end. This type of work requires precision and special technique. It is for welding that most welding machines have a mode for working with aluminum. It works on the following principle: the initial current power is increased to pierce the protective layer, and the final current power is reduced to seal the resulting crater.
How to set up the device
Let's look at the step-by-step instructions for beginners using the Ironman 200 AC/DC welding inverter as an example.
1) The leftmost function is the AC balance setting (CLEAN WD.), which has 2 polarities - minus and plus.
Our connection technology uses 50/50 polarity; the polarity changes depending on the type of task. For example, when welding pure aluminum, the balance is adjusted in the negative range. This way the metal, bath, and electrode will heat up less, and the seams will turn out thin and beautiful. Due to the low heating of the electrode, it can be sharpened more sharply.
For dirty aluminum, it is better to set the positive range, so the heating of the metal will be stronger, and the cleaning of the bath will be better.
Be careful: a positive half-wave has a detrimental effect on the tungsten electrode.
Based on the diameter of the electrode, the correct balance of alternating current is adjusted.
2) The next function (CURRENT) is the welding current setting. To weld aluminum, for example, 2 mm thick, it is enough to set the force to 60-65 A.
3) Third toggle switch (DOWN SLOPE) - crater filling setting (slow arc decay). Setting the arc decay time depends on the thickness of the metal. For 2 mm it is enough to set it to 3 seconds.
Source: https://tpspribor.ru/svarka/kak-pravil-no-varit-alyuminiy-argonom.html
Features of welding aluminum with argon
Aluminum is one of the most common metals, but at the same time one of the most difficult, since an oxide film is formed on it, which has a melting point higher than that of the metal itself. This causes difficulties when gas welding aluminum. In modern welding, there are several ways to weld it:
These methods can be carried out both in a protective gas environment and without it. Let us next consider how aluminum is welded with argon.
Argon is a noble inert gas, odorless and colorless, almost one and a half times heavier than air. It is too in demand for use in joining parts due to its availability, in comparison with other inert substances.
It is possible to cook without argon, but in this case oxidation of the molten metal occurs (when interacting with oxygen), which significantly affects the quality and aesthetics of the joint.
That is why gas welding of aluminum using this gas is a priority.
Difficulties of welding aluminum
Gas welding of aluminum is a rather complex process and this is due to the qualities of this metal. Welding aluminum with argon for beginners requires knowledge about the characteristics of this metal and skills when working with it. The main factors that interfere with the normal joining process, and every master should know all these nuances:
- poor-quality metal stripping before gas welding of aluminum is one of the most basic mistakes that novice welders make. In order to break the oxide layer on the metal surface, it is necessary to thoroughly clean it. For example, if dust, dirt and the top layer remain on the edge, then normal bonding is out of the question. The upper oxide layer melts at a temperature of more than 2000 degrees, and Al itself at a temperature of 660;
- argon welding of aluminum requires high energy costs. This is due to the high level of thermal conductivity and low melting point;
- an incorrectly set mode on the inverter can lead to failure, since aluminum melts at a low temperature;
- Due to the fact that the molten Al mass quickly crystallizes, it is necessary to weld the crater that forms during fusion at the end of the track. The unit for gas welding of aluminum has a special function that allows you to supply the conductor with increased current at the beginning of the process to pierce the Al film, and at the end to weld the crater.
Preparing aluminum for welding
From the above, we can conclude that the main stage in argon arc welding of aluminum is the highest quality preparation of the product itself. In order for the seam to fit perfectly, without any leaks or deformations, cleaning is required. This is done in several ways:
- the chemical method allows you to destroy the oxide film on the metal due to the action of such a solution: 50 grams of technical sodium and 45 grams of sodium fluoride must be dissolved in a liter of water. Stir until a homogeneous solution is obtained. After a minute of etching, the part must be rinsed under running water;
- The mechanical method involves the impact of additional tools on the part. Most often, they change the iron brush for cleaning workpieces. It is important that it is designed specifically for aluminum. Alternatively, you can use sandpaper. Regardless of the type of additional tooling, it is necessary that it be either new or used only after aluminum. If particles of another metal get into the scratches that appear from abrasiveness, this will significantly deteriorate the quality and final result of aluminum gas welding.
In addition to the workpieces, it is necessary to prepare the wire for welding aluminum with argon. It must also be degreased and soaked in technical sodium according to the same procedure. This will remove all excess molecules from the material and allow you to create a perfect Al alloy weld.
Equipment for gas welding of aluminum
When the product is ready for argon welding, you need to ensure that all the necessary components are available and that the equipment is configured. To complete the process, the following is required:
- apparatus;
- tungsten electrodes;
- additional Al wire;
- inert gas (in our case argon).
The apparatus used is a conventional torch, used for all types of gas welding, since aluminum is welded with direct current in an argon environment. Tungsten non-consumable electrodes come in different types, depending on the additives in their composition.
To distinguish them, multi-colored markings are applied to the end. The electrode must be sharpened before use. When an arc appears, a ball forms at its end.
The thickness of the conductor is selected depending on the thickness of the product; for example, for thin aluminum, conductors with a diameter of no more than 2 millimeters are suitable.
It is important to check all components necessary for gas welding of aluminum for expiration dates. Do not cook with expired materials.
Argon aluminum welding technology
In order to obtain a high-quality connection as a result of argon welding, it is necessary to follow all the rules when working. Firstly, it is important to prepare the material and wire, secondly, to set up the apparatus, and thirdly, to properly excite the arc and hold it until the end of the process.
How to properly set up equipment for gas welding of aluminum
Let's look at the example of a standard Al sheet, 2 mm thick. Always when connecting with argon, the inert gas flow is first supplied and adjusted, and then the current source is turned on.
Ideally, during an argon-arc connection of aluminum, about eight liters of shielding gas should be consumed indoors and one and a half times more if outdoors. But at the same time, it is important to remember about turbulence.
If you turn on a very high gas supply, it can “spin” and mix with air, which also should not be allowed. For this size of workpieces, a conductor with a diameter of 1.6-2.4 mm is suitable for welding with argon.
Aluminum welding with argon technology
It is possible to ensure high-quality connection of aluminum parts only by TIG welding. A regular electrode can weld aluminum alloy for strength, but it will require longer post-processing.
Welding aluminum with argon allows you to work with material of different thicknesses, creating neat seams with good sealing properties. This is especially in demand when repairing cars, boats or various containers.
But how to cook this specific material for the first time? How to set up equipment when welding aluminum? A short guide from the article and video lesson will help you master this complex matter.
What must be considered when argon welding aluminum?
Argon welding is quite universal, which allows you to join different thicknesses of materials using this method and work with alloys that are considered difficult to weld. The basis is an electric arc burning between a tungsten electrode and the product.
Its appearance is ensured by direct or alternating current supplied to the torch and the mass attached to the parts being welded. The inert gas acts as a protection for the weld pool.
But aluminum and its alloys have a number of specific features that need to be known and taken into account when welding.
One of the difficulties is the oxide film that forms on the surface of the material. It appears when metal interacts with oxygen. The film melts at a temperature of 2000 degrees. But aluminum itself begins to take on a liquid form after 500 degrees.
Therefore, by choosing too high a current and melting the oxide, it is impossible to weld. By setting small parameters on the device, it is not possible to begin the process of creating a weld pool at all. Therefore, argon arc welding of aluminum involves preliminary cleaning of the metal surface from oxide.
This is achieved with a special brush or solvent, after which it is necessary to immediately begin the welding process.
An additional difficulty is the hygroscopicity of the material. When the ambient humidity is high, aluminum absorbs some of the water from the air. When the product begins to be heated by an electric arc, the material being welded releases moisture to the surface.
This may affect the quality of seam formation, the density of contact with the product, and low-voltage pinching of the welder in contact with wet areas. Although you can cook with argon immediately, it is recommended to slightly heat the material with a gas burner at a temperature of 150 degrees.
This will allow excess moisture to evaporate and improve the welding process.
Argon welding of aluminum also requires good protection of the molten metal from external air. To do this, you need to set the correct gas flow. Insufficient supply of the latter will lead to foaming of the metal and burning of tungsten. Excessive argon purging will interfere with weld formation and will make the process more expensive.
Another difficulty for novice welders is the formation of a funnel at the end of the seam. If the arc is abruptly interrupted, a crater appears. Holding the torch in one place for a long time leads to unnecessary heating and expansion of the weld pool.
Therefore, argon-arc welding of aluminum alloys requires additional settings for the arc attenuation mode, which gradually reduces the current strength.
Taking into account these characteristics of the material, you can correctly set the voltage parameters and make a high-quality seam with your own hands.
Welding technology for beginners
The process of argon welding of aluminum is performed not with direct current, but with alternating current. This way you can achieve better results. It is better to start your first seam on the training surface:
- It is necessary to set the plates in a comfortable position. Edge cutting is performed according to the same parameters as other types of metals.
- It is advisable to heat the material to 150 degrees to remove moisture.
- The top refractory layer is removed with a brush. As an alternative, you can use a solvent.
- The burner is brought to the product so that there is 3 mm between the electrode and the surface. The button is pressed and the arc is ignited. The fluidity of aluminum depends on the impurities in the composition.
- If a small puddle of molten metal (weld pool) occurs, an additive can be supplied to the welding zone.
- The burner must be directed evenly, from right to left. Oscillatory movements will be needed in the case of a wide seam. On alternating current, a characteristic welding noise will be heard.
- When the seam is completed, the button is pressed and the arc fades out smoothly. The torch is held above the welding zone until gas flow has completely stopped.
Device setup and modes
TIG welding of aluminum is possible only where the machines support operation not only with direct current, but also with alternating current. Despite the frequency of voltage fluctuations, the best seam is obtained with the last setting. Polarity can be either direct or reverse. Voltage parameters can be set based on the thickness of the material:
Plate thickness, mm | Current strength, A | Diameter of tungsten electrode, mm |
1 | 30 — 40 | 1.6 |
1.5 | 45 — 60 | 2.3 |
2 | 70 — 80 | 2.3 |
3 | 90 — 120 | 3.2 |
It is important to install the current supply in a stepwise manner, with a smooth ignition, an ascending value during the welding process, and a gradual attenuation when combustion is completed. This will avoid creating a crater at the end of the connection.
The argon consumption during welding is set on the pressure gauge closest to the gas hose. Russian models need to be installed in the range from 6 to 11 liters. This is the error of the measuring device, which is brought to the optimal value only by practical means. If the pressure gauge is imported (German, Czech), then you can immediately supply 8 liters.
In the device settings, it is important to set the subsequent gas purging time after the arc stops burning. The duration of argon supply is set to five seconds, which gives enough time for the bath to solidify and cool the electrode.
Since aluminum melts relatively quickly, if you choose the wrong diameter of the filler wire, you may not have time to feed it into the welding zone and form a seam. Therefore, the thickness of the solder should be the same as the thickness of the plates being welded.
It is also necessary to be careful when choosing the chemical composition of the filler material. For example, a product made of duralumin cannot be welded with a rod for food-grade aluminum.
A table with filler wire numbers and its purpose can help:
Additive marking, no. | Purpose |
1070/1100 | AD1, AMts. |
5754 | For welding aluminum with magnesium admixture. |
1450 | For alloys used in aircraft construction. The additive is equipped with a titanium inclusion that strengthens the seam. |
5183 | For food containers and shipbuilding. |
5554 | For wheel rims and containers in the chemical industry. |
4043 | For alloys with silumin used in construction. |
Electrode selection
The technology of welding aluminum with argon also requires the correct choice of a tungsten electrode, the diameter of which should be as close as possible to the thickness of the parts being welded.
Sharpening is done in the classic way, but without a sharp tip, as is the case with stainless steel welding. During the first seconds of combustion, the electrode will take the shape of a drop at the end and the seam will have to be made this way. The projection from the nozzle is required to be 3-5 mm to avoid overheating of the tungsten.
When welding, small spatters of aluminum will stick to the electrode, requiring re-sharpening.
Learning to weld aluminum is not easy. But knowing the above principles and watching videos with lessons from experts, you can confidently try your hand at practice.
Source: https://svarkalegko.com/tehonology/kak-varit-alyuminij-argonodugovoj-svarkoj.html
Welding aluminum with argon for beginners
In world and domestic practice, there are two most popular methods of joining aluminum parts - TIG and MIG. The first abbreviation denotes the manual method of welding with a non-consumable electrode, the second is semi-automatic. This article will focus on the first method, because... The concept of argon-arc welding of aluminum and other metals implies exactly this.
Why is aluminum difficult to weld?
Experienced welders know that the Al welding process is one of the most difficult. Working with it requires the worker to have certain skills and, of course, knowledge. In this case, argon welding of aluminum is no exception. Below are some facts that a welder must know:
- Oxide film, which is the main “enemy” when welding. Its melting point is more than 2000 C, although aluminum itself begins to melt at 660 C. The oxidation of pure aluminum in air occurs very quickly, forming the same aluminum oxide Al2O3.
- It is necessary to clean the metal before welding.
This is the key to breaking the oxide layer. Does not change color when heated. It is difficult to monitor the degree of heating of the part, which is why, especially for beginners, burns are observed and molten metal leaks. - It takes a lot of energy. Unlike steels, volatile metal has high thermal conductivity, it is several times higher. Welding aluminum with argon requires a large amount of energy. Moreover, when connecting large parts, it will not be superfluous to preheat it. High thermal conductivity and low melting point can lead to burnout of parts.
- The need to fill the crater. And one more technological feature: after the end of the welding process, at the end of the seam, a crater is formed, this happens because the aluminum alloy quickly hardens. To ensure the elimination of this defect, a special mode is provided in welding machines. When welding is completed, increased current flows to the electrode. It is used to break through the oxide film at the beginning of welding, and to weld the crater formed at the end.
We recommend! Do-it-yourself welding of polypropylene sheets
Preparing metal for welding
Without preliminary preparation of the surface of the welded edges, it will be impossible to achieve a high-quality connection.
Mechanical method
The oxide film is cleaned using:
- sandpaper;
- scraper;
- metal wire brushes
It is advisable to use a brush with a stainless steel wire with a maximum diameter of 0.15 mm. When processing with emery, the metal may become contaminated, so the use of the last two methods is most preferable. They are carried out immediately before welding
Important ! Whatever brush you use, make sure it is used exclusively for aluminum.
The reason for this is the possibility of introducing particles of another metal, which in turn significantly reduces the reliability of the welded joint. The use of an attachment for an angle grinder or electric drill is not recommended, as it contributes to the introduction of oxygen into the metal. When strongly pressed, it destroys the structure, leaving pores in the aluminum, which can create additional difficulties during argon welding of aluminum. In industry, special brushes are used for these purposes.
Chemical method
The destruction of the oxide film is achieved by etching for 1 minute with the following composition:
- 1l. Water
- 50g. caustic soda
- 45 g sodium technical fluoride
Then you should rinse the workpieces in running water and light it.
Important! Chemical cleaning allows you to preserve the surface of aluminum and its properties for 3-4 days.
I would like to note that preparation requires not only the metal being welded itself, but also the filler rod in the form of aluminum wire. To obtain good results, it is recommended to perform the following operations:
- Solvent washing, no degreasing required;
- Etching at a temperature of 60-70 °C in a 15% nm technical sodium solution;
- Cold water rinsing;
- Drying;
- Calcination for 15-30 minutes. temperature 300 °C in atmospheric air
Necessary equipment for welding
We will not talk about the essence of the TIG welding method here; we will only note that tig welding of aluminum is feasible if you have:
- welding machine;
- tungsten electrode;
- protective gas (argon);
- filler wire.
Source: https://svarkagid.ru/tehnologii/svarka-alyuminiya-argonom.html
How to cook aluminum with argon
15.04.2019
There are several ways to permanently connect this capricious material; each has advantages and disadvantages. But reliable and aesthetic seams that do not require additional processing are created only by welding aluminum with argon. The success of the work is determined by the correct choice of equipment, consumables and knowledge of the nuances of the method.
Features of welding aluminum with argon
When performing work, you need to take into account the unusual characteristics of this metal:
- Due to increased chemical activity, the surface of aluminum upon contact with air is quickly covered with an oxide film. It melts at a temperature of more than 2000⁰C, and metal - 660⁰C. If hard pieces of film get into the seam, its strength will decrease.
- When welding aluminum, it is difficult to control the process, since its color does not change after melting.
- The material is hygroscopic, therefore it absorbs atmospheric moisture, which, when heated, evaporates from the surface, reducing the quality of the connection.
- Due to the high coefficient of linear expansion, the joint may become deformed and crack when cooling. To compensate for shrinkage, argon welding is carried out with increased wire consumption or the seam is modified.
- If the gas flow is incorrectly adjusted when performing argon welding of aluminum, it foams when there is a shortage, and when there is an excess, it makes it difficult to form a seam.
Necessary equipment and materials
To operate, you will need a device that produces alternating current, since welding aluminum with direct current using the argon method cannot be carried out. The best option would be an inverter with a TIG mode and a set of options allowing:
- ignite an arc without contact;
- weld a crater at the end of the seam;
- adjust current balance;
- set the period of time during which the argon supply continues after the arc is turned off.
To reduce gas consumption for welding aluminum, you need to acquire a torch with a gas lens (collet holder), inside of which a mesh is placed. When argon passes through the cells, protection of the welding site is improved at lower consumption. To install lenses, nozzles of several diameters are available; the larger the size, the more reliable the protection.
Source: https://svarkaprosto.ru/tehnologii/kak-varit-alyuminij-argonom
Welding aluminum with argon: step-by-step instructions for beginners, video
The most effective way to create a permanent connection of parts made of aluminum and alloys based on this metal, as practice shows, is welding aluminum with argon.
Any welding technology that involves the use of shielding gas requires the use of special equipment, as well as the welder having the appropriate knowledge, qualifications and experience in performing such work.
In addition, it is necessary to have at least basic knowledge in the field of metallurgy in order to understand what processes take place in the weld pool.
Aluminum argon arc welding process