铝合金压印连接运行工况图与微动磨损

Working condition diagram and fretting wear of aluminum alloy in clinch connection

通过对AA5182压印连接,制备一批压印连接试件,一部分用于静拉伸试验,平均失效载荷值为1 449 N,失效形式均为颈部断裂。另一部分用于微动试验,施加最大载荷力为1 350 N,应力比R=0.1,试件失效形式均为上板断裂,断裂方向垂直于加载力方向,断裂位于接头边缘处。对微动试验的运行工况图分析,可得:微动初期F-D曲线呈椭圆形,张开型,有明显弹塑性变形,材料刚度增加较快;循环次数逐渐增多F-D曲线呈近似直线型,塑性变形减弱,弹性协调为主,材料刚度增加减缓。

A batch of clinch joint specimens of AA5182 alloy were prepared. Some parts were used for static tensile test,the average failure load value is 1 449 N,and the failure mode is neck fracture. The other parts were used for the fretting test,the maximum load is 1 350 N and the stress ratio is R=0.1. The failure mode of the specimens is the upper sheet fracture,the fracture direction is perpendicular to the loading force direction,and the fracture is located at the edge of the joints. By analyzing the working condition diagram obtained by the fretting test,it can be known that the initial F-D curves are elliptical,open-type,with obvious elastoplastic deformation and fast growing of material stiffness;the F-D curves are approximately beeline as the number of cycles increased gradually. At the same time,the plastic deformation is weakened,the elastic coordination is dominant,and increasement of the material stiffness become slowly.