搭接长度对钛合金-芳纶纤维复合材料单搭接接头胶接性能的影响

采用钛合金与芳纶纤维复合材料制备不同搭接长度的单搭接接头。利用数字图像相关技术（DIC）、万能试验机等表征方法，对接头拉伸应变与极限载荷进行表征，研究了搭接长度对异质材料单搭接接头胶接性能与破坏模式的变化规律。结果表明，随着搭接长度的增加，单搭接接头极限载荷提升，胶接强度降低，高搭接长度接头出现渐进损伤；偏心弯矩引起的接头偏移减少，搭接部位纵向应变区域面积占比降低；芳纶纤维复合材料层间破坏模式增多，钛合金?胶层界面破坏模式减少，剥离复合材料层数增加。

Effect of Lap Length on Bonding Properties of Titanium Alloy/Aramid Fiber Composites Single Lap Joints

The single lap joints with different overlap lengths were fabricated by titanium alloy/aramid fiber composites,and their tensile strains and ultimate loads were characterized by DIC and universal testing machine.The effect of overlap length on the bonding properties and failure modes of the single lap joints of dissimilar materials was investigated.The results indicated that the ultimate load of single lap joints increased with an increase of overlap length,but their bonding strength decreased.The joints of high overlap length were damaged progressively.The joints rotation caused by the eccentric bending moment decreased,and the proportion of longitudinal strain area in overlap region was also reduced.Moreover,the fiber?tear failure of the composites increased,but the adhesive failure between the titanium alloy and adhesive layer decreased.In addition,the layer number of the stripped composites increased.