In welding, what is referred to as the ‘arc’?

The term 'arc' in welding specifically refers to the electrical channel of ionized gas that conducts current between the electrode and the workpiece. In the context of welding, an electric arc is created when a voltage is applied between the electrode and the base materials, which ionizes the air in the gap, allowing current to flow. This flow of electric current generates intense heat sufficient to melt the metal, which facilitates the process of fusion when the molten metal from the electrode and the parent material combine.

Understanding the nature of the arc is essential as it directly impacts the quality of the weld, including penetration depth, bead shape, and overall strength. The formation and stability of the arc are critical factors in successfully executing welds, making it a fundamental concept for anyone involved in welding practices. In contrast, other options might refer to different aspects of the welding process, such as the weld itself, protective measures, or thermal considerations, but none address the specific phenomenon of the arc.