Which two electrodes are most commonly used for GMAW?

The most commonly used electrodes for Gas Metal Arc Welding (GMAW) are those that provide a good balance of weld quality and cost-effectiveness, particularly in industry standards. The ER70 S-3 and ER70 S-6 electrodes are well-suited for general applications and are frequently utilized for both carbon steel and low-alloy steel welding.

ER70 S-3 is typically used for applications where moderate strength is sufficient and offers a good deposition rate. Meanwhile, ER70 S-6 provides slightly better chemical composition and mechanical properties, making it advantageous in more demanding situations that might require a higher strength or better toughness in the weld.

Both electrodes are suitable for various welding positions and allow for good bead appearance and weld integrity. The use of these electrodes also aligns with the requirements outlined in the Structural Welding Code, ensuring that the resulting welds meet necessary performance and safety standards.

In contrast, the other options consist of electrodes from different categories or standards, such as higher-strength electrodes that are not typically used for general GMAW applications or those that do not meet the balance of versatility and performance expected in most welding scenarios.