| With the deepening of fatigue research, researchers have found that there is a fatigue problem that is caused by fretting fatigue in the structure. Because the micro-movements may lead to significantly lower with the fatigue life of components and serious consequences. This effect is particularly significant in the connection. Thus, this paper studies the friction type high strength bolts connecting the lap fretting fatigue.Firstly, this paper studies fretting fatigue test by changing the stress value of the friction-type high-strength bolts connecting lap. The data points were fitted fretting fatigue life with the least square method and the three-parameter method. After co MPared with the experimental data, S-N curve with three-parameters is more accurate than the least square method to predict fretting fatigue life. Through the fracture morphology of SEM analysis, it was found that fatigue cracks connected sprouted from the middle to extend on both sides of the contact surface and the reason of connection failure is the micro-movements.Secondly, by ABAQUS finite element analysis of friction-type high-strength bolt connection lap gets the stress and relative displacement between the contact surfaces with different stress values. FFD comprehensive parameter method is used to predict the fretting fatigue crack initiation position. By co MPared with the experimental results obtained from numerical simulation, we found that the use of FFD comprehensive parameter can accurately predict fretting fatigue crack initiation test specimen location.Finally, the paper introduces FFD that is the decisive factor of fretting fatigue life to improve the traditional S-N curve. FFD-N curve with three-parameter method can accurately predict the fretting fatigue life. Using FFD-N curve can predict crack initiation position and simultaneously get their fretting fatigue life. |
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