Using the finite element method to find out that the reason of fracture is high cycle fatigue damage when the number of support plates is 10; and the main cause of blade fatigue is the unreasonable number of plate. The two optimization schemes which derived in Campbell figures are the number of support plates are 3 and 19. From the number of resonance points

the stress level and the theoretical life expectancy

the number of support plate 19 are better than 3. In order to verify the accuracy of the model

we calculated the fatigue life of turbine fan blades when the number of support plates is 10 and 3. The results show that the fatigue life of the two is short

which do not meet the actual requirements of the project. Finally

the number of support plate is 19.