Question

what is the primary function of filler metal in the welding process? a to protect the weld from atmospheric contamination b to remove impurities from the base metal c to join base metals by adding material to the weld joint d to create a molten pool by generating heat

Explanation:

• Option A: Protecting the weld from atmospheric contamination is the role of shielding gas or flux, not filler metal.
• Option B: Filler metal does not remove impurities from the base metal; that's more related to processes like flux action or metal refining.
• Option C: Filler metal is added to the weld joint to provide the material needed to fuse and join the base metals together, which matches its primary function.
• Option D: Generating heat to create a molten pool is done by the welding power source (like an arc or flame), not the filler metal.

Answer:

C. to join base metals by adding material to the weld joint