连接形式与基板厚度对自冲铆接头静力学性能的影响

Influence of Connection Form and Basic Plate Thickness on Static Mechanic Properties of Self-piercing Riveted Joints

为了研究连接形式与基板厚度对自冲铆接头静力学性能的影响,制备了双铆钉搭接长度40 mm的5052铝合金自冲铆接头,其中两组拉伸-剥离试样的基板厚度分别为1.5 mm(DAA)和2.0 mm(BBT),一组拉伸-剪切试样的基板厚度为2 mm(DR)。基于准静态力学试验,分析了各组接头的强度、刚度、失效形式以及能量吸收水平。结果表明:DR组失效载荷约为BBT组的2.8倍,BBT组失效载荷约为DAA组的1.9倍;DR组刚度大于BBT组和DAA组;BBT组弯矩一直大于DAA组。三组自冲铆接头的失效模式为:DAA组、BBT与DR组均为铆钉与上板从下板拉脱,上板两个铆钉头下陷。BBT组能量吸收值约为DR组的1.2倍,约为DAA组的1.9倍。

In order to study the influence of the connection form and the thickness of the base plate on the static performance of self-piercing riveted joints, 5052 aluminum alloy self piercing riveting joints of double rivet lap with length of 40 mm were prepared, in which the substrate thicknesses of the two groups of tensile-peeling samples were 1.5 mm （DAA） and 2.0 mm （BBT）, and substrate thickness of a set of tensile-shear sample was 2 mm （DR）. Based on quasi-static test, the strength, stiffness, failure mode, and energy absorption level of each joint were analyzed. The results show that the failure load of DR group is about 2.8 times of that of BBT group, and the failure load of BBT group is about 1.9 times of that of DAA group; the stiffness of DR group is greater than that of DAA group and BBT group; the bending moment of BBT group is greater than that of DAA group. The failure modes of three groups of self piercing riveting joints are that： rivets and upper sheets of DAA, BBT and DR group are pulled out from the upper sheets, and two rivet heads in the upper sheets sink. The energy absorption value of the BBT group is about 1.2 times of that of the DR group, and about 1.9 times that of DAA group.