What are the consequences of excessive heat input in GTAW?

Excessive heat input in Gas Tungsten Arc Welding (GTAW) can lead to significant issues, particularly warping, distortion, and a reduction in the mechanical properties of the weld. When heat is applied too intensely or for too long, the base metal can become overheated, which leads to structural changes in the material. This overheating can cause warping, where the metal bends or twists out of its intended form. Additionally, the heat can alter the microstructure of the weld metal, potentially lowering its strength and ductility. As a result, the weld may not be able to withstand the loads or stresses it was designed for, leading to potential failure in application.

In contrast, enhancing weld strength and durability, promoting uniform bead appearance, or increasing corrosion resistance would typically be associated with optimal heat input, not excessive heat. Thus, the emphasis on proper heat management is essential to achieving high-quality welds in GTAW.