Fatigue Crack Growth in a Solid Circular Shaft Under Fully Reversed Rotating Bending

摘要

The axle of a load train failed after 5.37 × 106 cycles from its service. Macro-fractography showed clearly the fatigue fracture. The stress distribution in the shaft revealed that the maximum alternating stress was considerably less than the material modified fatigue limit obtained at 107 cycles from the S–N diagram. Micro-fractography reported from the metallurgical laboratory proved the existence of a surface flaw. Ultimately, fatigue crack growth simulation was performed based on the simple Paris–Erdogan model for estimating the fatigue life of the defective axle. The results showed that the actual life of the axle could be satisfactorily predicted by means of the Paris–Erdogan model.