NOCTI Welding Practice Test 2025 – Complete Exam Prep

In Gas Tungsten Arc Welding (GTAW), also known as TIG welding, the choice of filler material is crucial, as it must be compatible with the base materials being welded. Both steel and aluminum can serve as filler materials in GTAW applications, depending on the specific requirements of the weld.

When welding steel, a filler rod made of a similar alloy composition to the base steel is typically used to ensure proper fusion and strength in the weld joint. For aluminum, a filler rod that matches the specific aluminum alloy being used is essential to achieving a strong and reliable weld. Thus, the inclusion of both materials as options reinforces the versatility of GTAW in joining different metals.

Using steel for welding steel and aluminum for welding aluminum exemplifies the adaptability of welding techniques to various materials. Therefore, it is accurate to state that both steel and aluminum are commonly used as filler materials in GTAW, depending on the application, which makes this choice correct.