基于循环塑性本构理论对端面齿联轴器螺栓紧固件进行循环载荷下的螺栓初期预紧力松弛分析,对端面齿联轴器各部件进行了三维有限元建模,根据材料的单轴循环应力控制试验数据进行计算参数设置.重点考虑螺纹根部材料塑性累积导致应力丧失,从而进一步引起预紧力衰减的过程.分析了螺栓初始预紧力随扭转循环载荷的变化,发现材料的塑性变形首先发生在第1道螺纹的根部,越接近被夹紧部位越容易发生屈服;预紧力随着扭转载荷循环次数的增加而降低,第1次扭转循环载荷导致预紧力降低的程度最为显著;预紧力松弛的速度随着循环加载而降低.同时,研究了预紧力松弛对端面齿和螺栓头接触应力、螺纹根部等效应力等特征的影响,为端面齿联轴器以及盘式周向拉杆转子的螺栓紧固件松弛的数值仿真研究奠定了基础. Based on the cyclic plastic constitutive theory, the initial pretension relaxation of the bolt under the cyclic load was analyzed. The three-dimensional finite element model was established for each component of the end gear coupling. According to the material’s uniaxial Cycle stress control test data to calculate the parameter settings.Considering the plastic root cause accumulation of stress leads to stress loss, which further leads to the process of preload attenuation.This paper analyzes the bolt initial preload with torsional cyclic load changes, found that the plastic deformation of the material First of all, it occurs at the root of the first thread. The closer it gets to the clamped part, the more prone to yielding. The pretightening force decreases with the increase of the number of torsional load cycles. The first cycle of torsional load results in the most significant decrease of pretightening force ; The relaxation speed of pre-tension decreases with the cyclic loading.At the same time, the influence of loose pre-tension on the contact stress of end tooth and bolt head and the equivalent stress of the root of screw thread is studied, The research on the numerical simulation of the bolt fasteners relaxation of the circumferential rod-rotor has laid the foundation.