铆接效应耦合的搭接接头受载应力与变形

The Interior Stress and Deformation of Loaded Lap Joints Consequent to Riveting Process

为有效改进航空搭接接头制造工艺,建立次弯曲效应下的中心线模型,并采用ABAQUS/Explicit与ABAQUS/Standard相结合的仿真方法,研究了飞机蒙皮上的多排铆钉搭接接头的铆接工艺及其影响下的结构受载内应力与变形。结果表明:采用适当的铆接参数可以极大地改善连接孔应力集中及结构疲劳特性。在疲劳载荷作用下,结构失效更容易发生在外排铆钉连接板的贴合面与孔表相交的位置,特别是靠镦粗钉头的连接板内。次弯曲会对结构受载后内部应力分布产生显著影响,但在孔的附近钉头覆盖下的区域应力特征受弯曲效应影响较小,铆接残余应力的影响仍然占主导地位。可见在工程应用中,更应该从连接孔周围挤压应力改善的角度寻求结构疲劳寿命增益。

To improve the manufacturing process of lap joints effectively,the stress and deformation of loaded lap joints with riveting process was investigated and a neutral line model of secondary bending and a simulation method were established using ABAQUS/Explicit and ABAQUS/Standard.Results show that by applying appropriate riveting parameters,the stress concentration around the hole and the subsequent fatigue of the joint was greatly improved.Under cyclic loading,the fatigue failure was more likely to occur in the outer rivet row on the fitting surface near the hole,especially in the sheet next to the driven rivet head.The secondary bending could obviously influence the internal stress distribution after riveting,except near the hole underneath the rivet head,where the riveting induced residual stress still shows a predominant effect.It can be seen that the removal of the stress created by riveting should be considered first for increasing the fatigue life of lap joints for an engineering application.