What is the purpose of using filler rods in gas tungsten arc welding?

In gas tungsten arc welding (GTAW), filler rods play a crucial role in the welding process. Their primary purpose is to add material to the weld joint, which helps create a strong and cohesive bond between the two pieces being welded. When welding, especially with thicker materials, a filler rod is introduced into the molten weld pool to supplement the base metals being joined. This ensures that enough material is present to achieve the desired joint strength and integrity. It is particularly important in applications where the weld must withstand significant loads or stresses.

While filler rods can influence other aspects of the welding process, such as arc stability or protection from contamination, their main function is to provide the necessary additional material to fill the joint gap and enhance the mechanical properties of the weld.