Considering the difficulty in calculating the stress concentration factor of mortise of a disk and the error of life is big by using the traditional stress-life method

an improved stress-life method is proposed to compute the life of disks.It includes the concept of stress correction coefficient

a new method to determine the stress concentration factor of mortise of a disk and a new method for correcting the stress ratio.When once the stress correction coefficient of the bars was computed

the improved Stress-Life method can be used to calculate disk's life with the experimental data of bars without notch

at the same time

the influence of the stress concentration is also considered.Then a new stress-life probabilistic model is built for the purpose of life reliability analysis.Finally

the fatigue life reliability of a fan disk is analyzed by the method given

and the computational results fit well with experimental ones.