Welding current is transferred from the electrode holder and into the workpiece through the
A. base metal
B. wire core of the electrode
C. flux coating
D. gas shield
The correct answer and explanation is:
The correct answer is B. wire core of the electrode.
Welding current is transferred from the electrode holder into the workpiece primarily through the wire core of the electrode. In welding, the electrode serves as the conduit for the current to flow from the welding machine to the workpiece. The wire core of the electrode is designed to carry the current from the electrode holder, where it is supplied, and deliver it to the weld pool formed on the workpiece.
The wire core is made of a material that is conductive, typically mild steel, to ensure efficient transfer of electrical energy. As the current flows through the wire core, it melts, allowing the weld metal to form and bond the two pieces of material being welded. The flux coating that surrounds the wire core serves different purposes, such as stabilizing the arc, shielding the molten pool from contaminants, and forming a slag that helps protect the cooling weld from oxidation.
The base metal refers to the material that is being welded, not the medium through which the current flows. Similarly, the gas shield, commonly used in processes like MIG and TIG welding, helps protect the weld area from atmospheric contamination but does not conduct the welding current.
Thus, the wire core of the electrode is the essential part for transferring the welding current to the workpiece, allowing the welding process to be completed.