Why is tungsten preferred for welding aluminum and magnesium?

Tungsten is preferred for welding aluminum and magnesium primarily because it provides great arc stability. The unique properties of tungsten, including its high melting point and excellent electrical conductivity, make it particularly effective for producing a consistent and stable arc during the welding process. This stability is critical when working with non-ferrous metals like aluminum and magnesium, as it helps in achieving a smooth and controlled weld process, reducing the likelihood of defects such as porosity or inclusions.

The quality of the arc directly affects how well the gas tungsten arc welding (GTAW) technique can perform. A stable arc allows the welder to maintain a consistent heat input to the base materials, which is essential for obtaining good penetration and minimizing distortion in the welded parts. Therefore, the arc stability that tungsten provides is a key reason for its preference in welding applications involving aluminum and magnesium.