Modeling of crack growth on 16MnR steel notched compact tension specimen

Fatigue crack growth was modeled for 16MnR steel notched compact tension specimen on the condition of Mode I cyclic loading with different stress ratios. The crack growth rate is determined by material damage during crack initiation at the notch and crack propagation. In the paper, a new cyclic plasticity model was introduced to describe cyclic stress-strain response near the notch properly, and the stress-strain field around the notch was calculated. Crack growth behavior in notch plastic zone was predicted by using a new multi-axial fatigue criterion to evaluate the fatigue initiation damage and growth damage near the notch. The modeling results are agreed with experimental data. The results show that when stress ratio is 0.1, crack growth rate near the notch accelerates monotonically with the increase of crack length. When stress ratio is equal to -1, crack growth rate near the notch decreases initially and then increases with the increase of crack length.