GTAW WLD 150 Welding And Joining Practice Test

Notch effect describes how geometry itself concentrates stress. When there’s an abrupt change in section thickness or continuity, the load path is disrupted and the local stress rises above the nominal value, creating a hotspot where cracks can initiate. That geometric-driven concentration is exactly what the term notch effect captures. Residual stress is a separate idea: it’s the internal stress locked into a material after processing or welding and cooling, present even without any external load. It can influence how a notch behaves, but it isn’t the description of the concentration caused by the geometry itself. Buckling is a stability failure under compression, and arc blow is the welding arc wandering due to magnetic effects—neither describes the notch-driven stress concentration.