Argon arc welding (TIG welding), as a high-precision welding technique, uses an electric arc to generate a heat source that relies on a tungsten electrode for formation and stabilization. The tungsten electrode itself does not melt, but provides the core functions of current conduction and arc discharge under the protection of an inert gas.
Specifically, the working principle can be understood from the following aspects:
Current conduction and arc formation
The welding power supply conducts current to the workpiece through a tungsten electrode, forming an arc between the electrode and the workpiece. The current is ionized through the air or shielding gas gap, creating a high-temperature plasma channel with arc temperatures reaching thousands of degrees Celsius. This high temperature causes the workpiece to melt locally, creating a melt pool that enables welding.
Inert gas protection
Argon arc welding uses high-purity inert gas (usually argon) to cover the welding area, preventing oxygen and nitrogen in the air from contacting the weld pool, and avoiding welding defects such as oxidation and nitriding. The tungsten electrode is located in the shielding gas stream, ensuring that the arc is stable and the electrode surface is not easily corroded.
Electrode material properties
Tungsten has an extremely high melting point (about 3410°C) and excellent conductivity, allowing the electrode to maintain its shape and properties in a strong arc without being consumed by melting. The shape of the electrode tip (e.g., tipping angle or spheroidization) affects the stability and concentration of the arc, which can be adjusted according to welding requirements for different applications.
Arc starting method
There are various ignition methods of electric arcs, including high-frequency arcing, contact arcing, and boost arcing. High-frequency arcing ionizes the gas through high-frequency and high-pressure pulses, and ignites the arc without contact. contact arcing is when the electrode is in short contact with the workpiece and then pulls apart to form an arc; The boost arc is completed by the power supply to quickly increase the voltage. Different equipment and processes choose different arcing methods to achieve safe and reliable welding start-up.
Arc control and heat input regulation
By controlling the welding current, electrode shape and shielding gas flow, the shape of the arc and heat input can be adjusted, affecting the size of the weld pool and weld formation. The stability of the tungsten electrode directly determines the continuity and uniformity of the arc, which in turn affects the welding quality.
More details of tungsten electrodes, please visit website: http://tungsten.com.cn/tungsten-electrodes.html
Please contact CHINATUNGSTEN for inquiry and order of tungsten needles:
Email: sales@chinatungsten.com
Tel.: +86 592 5129595
