Abstract:

The single-peak overload retardation effect in fatigue crack propagation of small cracks is studied by experiments by using LY12CZ aluminum alloy specimens with small crack at the notch. It is found that for small cracks the overload retardation effect is similar to that for long cracks but it is more sensitive to overload for the former ease. Prediction calculations using the closure model are done, the prediction are satisfactory for engineering purpose.

Key words: small crack, crack growth, single-peak overload retardation effect