What role does the filler material play in the GTAW process?

In the Gas Tungsten Arc Welding (GTAW) process, the filler material plays a crucial role in enhancing the properties of the welded joint. It adds both volume and strength to the weld joint, allowing for proper bonding between the base materials being joined. The filler material is used when the thickness of the base metals requires additional material to achieve a strong and complete weld, filling gaps and ensuring a robust connection. This allows for improvements in the integrity and durability of the final weld, making it essential in applications where structural strength is paramount.

The options that suggest the filler material is only for decoration, is unnecessary, or decreases heat input do not align with the practical uses and benefits of the filler material in the welding process. The filler material must be carefully selected to match the base metals being joined, ensuring compatibility and optimal performance in the finished weld.