异种材料单搭接接头力学性能

为研究异种材料在不同连接方式下的失效特点并促进胶铆接头在工程中的应用普及，本文以碳纤维/铝合金单搭接接头为研究对象，对胶接、铆接和胶铆混合连接接头的静态拉伸力学性能开展了试验研究。研究中以胶粘剂材料和铆钉材料为研究变量，首先对单搭接胶接接头和铆接接头的拉伸力学行为进行讨论，并从中分别选择了两种胶粘剂和铆钉材料进行组合，重点研究了胶铆接头的交互作用，同时也对铆接方向对接头的影响进行了探讨。研究结果表明，从载荷-位移曲线上看，胶接接头呈现脆性的断裂特点，铆接接头呈现韧性的断裂特点，胶铆接头综合了胶接和铆接的断裂特点，且胶粘剂在其过程中先断裂失效。另外，铆接方向对铆接和胶铆接头的力学性能有重要影响；当铆钉从碳板侧插入时，其力学性能会优于铆钉从铝板侧插入制备的连接接头。本研究中，强胶弱铆组合制备的胶铆接头表现出最强的正交互作用，因此其材料的利用率最高。本研究为工程实际中复合材料与金属材料间的连接提供了设计依据和指导方法。

Study on mechanical properties of dissimilar single lap joints

In order to study the failure characteristics of dissimilar materials under different connection methods and promote the application of hybrid joint in engineering, the static tensile mechanical properties of CFRP/Aluminum single lap joints were studied, including adhesive, rivet and hybrid joints. Different kinds of adhesive and rivet were considered in adhesive joints and rivet joints and tensile mechanical properties of them were discussed firstly. Then, two kinds of them were selected respectively for the preparation of hybrid joints where the interactive effect was studied. Besides, the effect of riveting direction on the mechanical properties of rivet and hybrid joints were analyzed. The results show that from the characteristics of load-displacement of joints, adhesive joint presents the character of brittle fracture, rivet joint shows the ductile fracture characteristics and hybrid joint includes both characteristics where the adhesive layer will fracture firstly. Besides, the riveting direction has an important influence on the mechanical properties of riveted and hybrid joints. The joint with the riveting insertion from the CFRP substrate side exhibits better mechanical performance than that from the aluminum substrate side. In the study of hybrid joints, the combination of strong adhesive and weak riveting show the strongest positive interaction so that its material utilization rate is the highest. The study can provide some insights for the connection design between composite and metal materials in practice.