Selecting the right electrode depends on the welding current (AC or DC) and the base material. For instance, Thoriated Tungsten (WT20) is excellent for DC welding of stainless steel, while Ceriated Tungsten (WC20) is a non-radioactive alternative suitable for low-current DC welding. For AC welding of aluminum, Zirconiated Tungsten (WZ8) or Pure Tungsten (WP) is preferred to maintain a balled tip. Always verify the color coding (e.g., Red for Thoriated, Green for Pure, Grey for Ceriated) to ensure it matches international standards like ISO 6848 or AWS A5.12.