Fatigue crack growth experiments on specimens subjected to monotonic large scale yielding

Fatigue crack growth behavior was investigated for through thickness long cracks in two different geometries at monotonic large scale yielding in a stainless steel 316L. Finite element computations on the coupling between the applied load, the crack length and the crack tip opening displacement, δ, were conducted. These coupling equations were used to control Δδ in situ in the experiments based on the potential drop measured crack length. The Δδ was able to characterize and correlate the fatigue crack growth load state for the present geometries and loads. Also the stress-intensity factor range, ΔKI, could predict the growth rates due to large isotropic hardening at cyclic conditions and absence of crack closure.