Argon arc welding is a kind of electric arc welding. Its peculiarity lies in the fact that the welding process takes place in a protective gas environment, which prevents the oxidation of the metal.
The zone that is treated with shielding gas includes the following elements: the end of the electrode and filler material, a certain section of the seam and the heat-affected zone. Argon is a neutral inert gas that does not interact with the metal during welding and is supplied through a special nozzle of the torch holder. By the name of the gas involved in the technological process, this type of connection of parts was named.
TIG welding equipment includes a non-consumable electrode, which is traditionally made of tungsten. This refractory metal has all the required qualities and characteristics, so it is often used in this type of welding.
In this case, the filler material is supplied in the form of a wire or rod, which during the technological process is periodically immersed in the weld pool. During operation, the electrode is held by a special holder, which is installed inside the nozzle intended for supplyingargon gas to the zone where argon arc welding is carried out. The equipment, accordingly, must withstand both the electric current passing through the electrodes and the thermal effects from the use of argon.
However, electrodes are produced not only from tungsten. They can also be made from stainless steel and aluminium. In this regard, argon arc welding is divided into 2 types:
- Fusible.
- With non-consumable electrode.
Argon arc welding can be manual and automatic. In automatic welding, only an electrode wire is used, and manual welding can be done with a non-consumable electrode.
Technological process of argon arc welding.
Because inert gases do not interact with metals, and because they are on average 38% heavier than the oxygen used in welding, argon will easily displace air with unwanted impurities from the welding zone. This avoids unwanted oxidation of the resulting seam, which significantly improves the quality of the product and its aesthetic qualities.
Electric current is passed through the electrodes to the parts to be welded. Simultaneously with the beginning of the passage of current through the part, the supply of argon through the burner nozzle begins. The process of entering the welding zone of the filler material is started, which melts under the action of heat released from the passage of current.
Because the argon environment does not allow arcing,you need to use a special device called an oscillator. This device provides reliable arc ignition with high-frequency pulses, and also increases the stabilization of the arc discharge at the moment of polarity reversal.
The advantages of TIG welding are:
- Efficiency.
- Weld thickness thin.
- Possibility of welding parts without filler material.
