Numerical Simulation for Optimizing Hole Utilization in Crack Repair in Fretting Fatigue

This study investigates the stop-hole technique for crack repairs in structural parts subjected to fretting fatigue. The drilling of a hole at the crack tip relieves the concentration of stresses around the crack, which prevents further growth. The maximum von Mises stress is considerably reduced by a stop-hole, as can be seen from the analysis. The configuration with a double stop-hole reduces it to 641 MPa with a 50 µm radius. An exploration of different radii shows that a higher radius value increases stress relief, while the best range is between 60–80 µm. To see exactly how this optimal range improves fatigue life, the number of cycles to crack initiation was computed; the optimal range thus significantly extends the repaired component’s lifetime. These findings suggest that stop-hole design optimization may be required to achieve enhanced durability for extending the service life of a fatigued component.