Weld Fatigue Life Calculator
A simplified engineering tool to estimate the fatigue life (cycles to failure) of a welded joint subjected to repeated loading.
The Silent Killer: Metal Fatigue
Fatigue is the weakening of a material caused by repeatedly applied loads. It is the most common source of failure in mechanical components. A welded joint that can easily handle a single, heavy load might fail after thousands of cycles of a much smaller load. This is why fatigue analysis is critical for components that experience vibration or cyclic stress, such as in bridges, vehicles, aircraft, and machinery.
The S-N Curve
The relationship between stress (S) and the number of cycles to failure (N) is represented by an S-N curve. This calculator uses a simplified version of this relationship, known as Basquin's equation, to provide an estimate. Welded joints are particularly susceptible to fatigue because the weld toe acts as a stress concentrator, initiating cracks that grow with each load cycle.