During which welding process is heat generated by an electric arc?

TIG welding, also known as Gas Tungsten Arc Welding (GTAW), generates heat through an electric arc created between a non-consumable tungsten electrode and the workpiece. The electric arc produces the necessary heat to melt the base metal and the filler rod (if used), enabling the formation of a strong weld joint. The process relies on the precision of the arc to control the weld puddle and ensure a high-quality finish.

Oxy-fuel welding, on the other hand, generates heat through the combustion of gas, typically acetylene combined with oxygen, rather than an electric arc. Therefore, this method does not involve the characteristics that define arc welding processes. Thus, the focus solely on the electric arc in the context of heat generation confirms that TIG welding is the correct answer for this question.