13th International Conference on Fracture June 16–21, 2013, Beijing, China -4- This paper the finite element model of the design life of the times, a major concern under constant stress amplitude fatigue damage D (design life and the useful life of the ratio), the expression can be expressed as (4). Safety factor S (in a given design life, the failure probability), the fatigue life of F (member fatigue failure when the number of load cycles). A D L D L = （4） D—Fatigue damage, DL —Fatigue design life, AL —Available fatigue life. As can be seen from Figure 3 to 5 leads to the difference in coefficient of the contact surface of the anti-friction, after the same number of times in the cycle as the anti-friction coefficient increases effective fatigue life is gradually reduced, resulting in increased fatigue damage due to the contact surface of the processing in different ways, The safety factor is gradually reduced. 0.3 0.4 0.5 0.6 600000000 605000000 610000000 615000000 F(cycle) μ (N.m) 0.2 0.3 0.4 0.5 0.6 0.00326 0.00327 0.00328 0.00329 0.00330 0.00331 0.00332 0.00333 D(%) μ (N.m) Fig 3 Fatigue life under different friction factor Fig 4 Fatigue damage under different friction coefficient 0.3 0.4 0.5 0.6 1.205 1.206 1.207 1.208 1.209 1.210 1.211 1.212 1.213 1.214 Safe factor( %) μ (N.m) Fig 5 Safe factor with different friction factor The different friction coefficients reflect the different processing side, the increase in friction coefficient can effectively reduce the relative slippage between the connecting plate, but so that the contact surface between the geometric discontinuity degree increases, resulting in a discontinuous area near the nominal stress value increases, The fatigue crack growth faster, reduce the safety factor of the structure[9] . As can be seen from Figure 6 to 8 with the temperature increasing the effective life of the same times in the cycle after the fatigue decreased, resulting in increase in the fatigue damage in the function of temperature, the safety factor of the structure decreases.
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