不同胶层厚度单搭接接头剪切试验与强度预测

Strength of Adhesively Bonded Single Lap for Differential Bondline Thickness and Tension Loading Prediction

对不同胶层厚度的单搭接胶接接头进行拉伸载荷的剪切试验,对比胶层厚度以及胶瘤等因素对搭接接头强度的影响,通过有限元数值仿真,模拟不同胶层厚度试验件在接头破坏位置附近的等效应力情况,得出随胶层厚度的增加接头强度逐渐减小、端部胶瘤降低了粘接表面应力峰值从而提高接头强度等结论。同时引用Hart-Sm ith弯矩系数计算出较厚胶层单搭接接头强度的保守值。

Adhesively bonded lap is used extensively in the manufacture of automotive structures.In order to explore the strength of the structures with lap joints,the adhesively bonded single lap joints with differential bondline thickness were tested in tension loading which creates shear across the bondline.Various parameters were investigated such as the bondline thickness and spew fillet.The equivalent stress was obtained through finite element analysis to define the effect of spew fillet for thick bondline,which helped to get the conclusions that strength of single lap was decreasing as bondline thickness increasing and spew fillet could reduce the peak value of stress so as to enhance the strength of lap joints.Hart-Smith factor was used to compute the tension load of single lap joints,which helped to get conservative prediction of strength.