Which combination of arc current and travel speed is recommended for stainless steel welding?

• A. Low current, slower travel
• B. Low current, faster travel
• C. High current, slower travel
• D. High current, faster travel

Answer: (B)

Minimizing heat input is the key idea when GTAW welding stainless steel. Heat input per unit length increases with current and decreases with travel speed, so using a lower arc current while moving the torch faster reduces the energy absorbed by the metal. This helps prevent distortion, burn-through, and excessive growth of the heat-affected zone, and it also helps avoid sensitization (carbide precipitation) that can decrease corrosion resistance. With stainless, you want enough fusion without overheating, so a lower current paired with faster travel typically gives better control over the weld bead and its properties. High current or slow travel tends to overheat the workpiece, increasing the risk of distortion and adverse metallurgical effects.