Argon arc welding is a type of electric arc welding. Its peculiarity lies in the fact that the welding process takes place in a shielding gas medium, which prevents the oxidation of the metal.
The following elements are included in the zone that is treated with shielding gas: the end of the electrode and filler material, a specific section of the seam and the heat-affected zone. Argon is a neutral inert gas that does not interact with metal during welding and is supplied through a special nozzle of the burner holder. By the name of the gas involved in the process, this type of connection of parts was named.
Equipment for argon arc welding 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 is periodically immersed in the weld pool during the process. During operation, the electrode is held by means of a special holder, which is installed inside the nozzle designed to supply argon 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 effect from the use of argon.
However, not only electrodes are produced from tungsten. They can also be made of stainless steel and aluminum. In this regard, argon arc welding is divided into 2 types:
- With consumable electrode.
- With non-consumable electrode.
Argon arc welding is manual and automatic. In automatic welding, only an electrode wire is used, and manual welding can be performed with a non-consumable electrode.
The process of argon arc welding.
Since inert gases do not interact with metals, and also due to the fact that they are on average 38% heavier than the oxygen used in welding, argon will easily displace air with undesirable impurities from the welding zone. This avoids the undesirable oxidation of the resulting weld, 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 through the current part, the flow of argon through the nozzle of the burner begins. The process of entering the weld zone of the filler material is started, which melts under the action of heat generated from the passage of current.
Since the argon medium does not allow arcing, it is necessary to use a special device called an oscillator. This device provides reliable ignition of the arc using high-frequency pulses, and also increases the stabilization of the arc discharge at the moment of polarity reversal.
The advantages possessed by argon arc welding are:
- Efficiency.
- Small weld thickness .
- Possibility of welding parts without the participation of filler material.