Abstract
Validity of the fatigue crack growth model in the first grain boundary adjacent notch root, which corresponds to the fatigue crack nucleation region, proposed by some of authors are investigated by comparing in-situ observed results by applying servo hydraulic fatigue test machine with scanning electric microscope (SEM). Besides, fatigue crack growth curves in the first grain boundary are measured and compared with the estimation results by the numerical simulation code FLARP into which the model is implemented. It is confirmed the validity of the proposed model and FLARP enables to estimate the fatigue crack growth curve in the first grain boundary.
