Abstract
In order to evaluate the effect of etch-pits on long fatigue life property of SUS304TP, rotating bending fatigue tests were carried out using the specimen, which had a few artificial corrosion pits. Stress intensity factor was used for the evaluation of etch-pit. Stress intensity factor was calculated by the pit diameter at surface and pit depth which were obtained by optical microscope observations or it was calculated by the pit area on fracture surface which obtained by SEM observations. As a result, the stress intensity factor of the pit bottom could be evaluated on the safety side by using optical microscope.
