What polarity is commonly used for welding stainless steel?

The commonly used polarity for welding stainless steel is DCEN, or Direct Current Electrode Negative. This polarity allows for better heat control and penetration when welding stainless steel. In the DCEN configuration, the majority of the heat is concentrated on the workpiece, which promotes a more efficient fusion with the base material. This is particularly important in stainless steel welding, where maintaining the material’s chemical integrity and preventing overheating are crucial to avoid issues such as distortion, excessive warping, and altering the material properties.

High-frequency AC is sometimes utilized to initiate the arc, but the dominant aspect of using DCEN is its effectiveness in providing the necessary heat and stability during the welding process. This balance helps achieve a clean weld with minimized contamination, which is essential in maintaining the stainless steel’s corrosion-resistance properties.

In contrast, other polarities and methods listed do not provide the same benefits as DCEN when welding stainless steel. Using AC with high voltage can produce a less stable arc and lead to inconsistent heat distribution. Using DC positive only can result in excessive heat directed at the electrode rather than the workpiece, which may cause problems during the welding process. Direct current at low voltage might not provide enough energy to create the necessary arc stability for effective welding.