When ER70S-2 is alloyed with silicon, aluminum and manganese, their role is to act as:

When ER70S-2 is alloyed with silicon, aluminum and manganese, their role is to act as:

• A. stabilizers
• B. deoxidizers
• C. lubricators
• D. indicators

Answer: (B)

Oxygen in the molten weld pool can cause porosity and oxide inclusions, so welding wires are designed to remove it. Silicon, aluminum, and manganese act as deoxidizers: they readily react with dissolved oxygen to form stable oxides (SiO2, Al2O3, MnO). These oxide compounds either become part of the slag or float out of the melt, decreasing the oxygen level in the weld metal and improving porosity-free, cleaner welds. The other roles don’t describe how these elements function in the wire’s chemistry—their job here is specifically to deoxidize the molten metal.

Oxygen in the molten weld pool can cause porosity and oxide inclusions, so welding wires are designed to remove it. Silicon, aluminum, and manganese act as deoxidizers: they readily react with dissolved oxygen to form stable oxides (SiO2, Al2O3, MnO). These oxide compounds either become part of the slag or float out of the melt, decreasing the oxygen level in the weld metal and improving porosity-free, cleaner welds. The other roles don’t describe how these elements function in the wire’s chemistry—their job here is specifically to deoxidize the molten metal.