Which material is commonly used as a filler wire in MIG welding?

The material commonly used as a filler wire in MIG welding is ER70S-6. This designation indicates that it is a specific type of welding wire suited for general-purpose welding, particularly for mild and low alloy steels. The "ER" stands for "Electrode Rod," while "70" indicates the tensile strength of the filler metal in thousands of psi, which means it can withstand significant stress and strain. The "S" signifies that it is a solid wire, and the "-6" indicates added deoxidizers, allowing for effective welding in various conditions, including ones with some surface contamination.

ER70S-6 is favored for its versatility and strong performance, making it particularly effective for welding applications in both flat and vertical positions. Its ability to produce high-quality welds with good penetration and minimal spatter enhances its popularity among welders.

Other filler wires like ER90S-1, ER308L, and ER4-5 are suited for more specialized applications. ER90S-1 is designed for high-strength steel welding, which makes it less common for general MIG applications. ER308L is primarily used for stainless steel and is not as widely applicable as ER70S-6. Similarly, ER4-5 is not