Two-Dimensional Surface Fatigue Crack Propagation and its Finite Element Simulation

Abstract

Fatigue crack growth rate at the plane stress is predicted by Paris equation, associating it with the stress intensity factor (SIF), generalized parameter of the elastic stress field near the crack tip. The finite element method allows modelling of the incremental crack growth in the plates, where the finite element grid should be re-meshed on each crack growth step fitting the first principal stress planes. However, the linear fracture mechanics format (LEFM) based evaluation of the two-dimensional fatigue cracks does not provide always the correct crack front assessment and appropriate life-predictions. It is shown that approach using the damage accumulation simulation and strain-life criterion may be promising in analysis of the two-dimensional cracks. Application of the approach is illustrated. The simulation results are in good agreement with the experimental data.