复合材料混合连接结构拉伸性能与影响因素分析

胶螺混合连接设计适当,能够提高结构的连接效率.针对复合材料胶螺(螺钉)混合连接结构中存在的分析与设计问题,在ABAQUS软件平台上建立了损伤累积三维有限元模型,其中考虑了胶层物理非线性以及非线性接触等问题,连接结构拉伸强度及损伤破坏过程的计算结果与试验结果基本吻合,证明了所建模型的有效性.在此基础上,研究了复合材料层合板端头翻边、胶层厚度、胶层韧性以及接触面摩擦系数等因素的影响.结果表明:复合材料层合板端头翻边对混合连接结构具有增强作用,能够提高结构的拉伸强度;韧性胶层能够提高结构的拉伸强度,但胶层厚度对结构的强度基本没有影响;螺钉杆与连接孔接触面间摩擦系数越大,连接结构的拉伸强度越高.

Analysis on tensile properties and influence factors of composite hybrid joints

Proper bolted or screw / bonded hybrid joint design can improve the structure efficiency. In order to solve the analysis and design problems that exist in screw / bonded hybrid composite joint structures, a 3D damage accumulation finite element analysis (FEA) model was established based on the software of ABAQUS. Non-linear properties of the adhesives and non-linear touch problems were included in this model. The analysis results of the tensile strength and damage propagation and failure of the joint structures agree with the test results. And the model effectiveness was proved. Then the influence factors such as the flange at the tip of the laminates, adhesive film thickness, adhesive toughness and contact surface friction coefficients on the joint tensile properties were studied. The results show that the flange at the laminate tip can reinforce the hybrid joint structures and improve their tensile strength. Adhesive with high toughness can improve the joint tensile strength and the film thickness almost has no effect on the strength. Higher friction coefficient between the screw pin and the hole surface can give greater joint tensile strength.