Considering the flaw of precision in forecasting the medium-long and long life of disks and simulation specimen with volume method based on the strain life model

volume method based on the stress life model was proposed to compute the life of disks

which considered the size effect. The maximum stress and stress ratio have been taken into the life reliability computation of the disk as parameters. Then the fatigue life reliability of a disk simulation specimen was analyzed by the method given. The difference between computational median life in the method and the experimental median life is only 14%

and they fit well with each other. While the computational median life in the strain based method is only sixteenth of the experimental median life. It is shown that volume method based on the stress life model which considering the size effect can be used to estimate the probabilistic life of the medium-long and long life of disks and simulation specimen.