Abstract
It is well known that the fatigue failure of metallic materials will occur due to the initiation of cracks and their subsequent growth. However, the number of crack nuclei is not provided deterministically and the number is not so small in many cases of engineering application. In these cases, the number of initiated cracks is also randomly variable and this should be taken into account in the evaluation of crack coalescence. In the present study, based on the numbers of initiated cracks, a statistical evaluation was made of the coalescence of cracks as a function of the number of stress cycles, and the fatigue life distribution was probabilistically derived from the above evaluation assuming that failure occurs immediately after the coalescence of cracks. The analytical results obtained are in good agreement with the experimental results of fatigue life distribution.
