碳纤维/铝合金电磁自冲铆-胶粘复合连接机理与失效研究

随着各种轻质材料在汽车车身上应用逐渐增多，异种材料之间的连接问题日益凸显，制约了汽车轻量化制造的发展。多种连接技术的交叉融合和复合应用是解决多材料可靠连接的有效手段，也是异种材料连接技术的发展趋势。本项目针对汽车上颇具应用前景的两种轻质材料—碳纤维复合材料和铝合金的连接问题，提出电磁自冲铆-胶粘复合连接技术，从结构设计、机理揭示和性能评价三个层面展开深入系统研究，优化连接工艺及结构参数，获取典型工艺参数下接头的最佳结构形式；建立电磁-热-力多场耦合数值模型，分析高速冲击作用下铆钉与胶层的动态响应及碳纤维/铝合金结构的损伤与强化机制，揭示电磁自冲铆-胶粘复合连接机理；研究接头在实际服役条件下的性能及失效行为，揭示铆钉与胶层的耦合失效机制，建立接头服役寿命模型。研究成果将进一步完善异种材料连接技术的理论基础，为开发出性能可靠的胶铆复合连接技术提供方法支持，为我国汽车轻量化制造的发展做出贡献。

With the increasing application of various lightweight materials in automobile body, the connection problem between these materials has been increasingly emerging, which has restricted the development of automotive lightweight manufacturing. The cross fusion and complex application of multiple joining technologies is an effective mean to solve the multi-material reliable connection problem, and is also the development trend of dissimilar material joining technologies. This project is aimed at the connection of two promising lightweight materials in automobiles--CFRP and aluminum alloy. Electromagnetic self-piercing riveted-bonded hybrid joining technology is proposed, and carries out in-depth and systematic research from three aspects: structure design, mechanism disclosure and performance evaluation. The joining process and structure parameters are optimized to obtain the best structural from of the joint under the typical process parameters. An electromagnetic-thermal-force multi-field coupling numerical model is established. The dynamic response of rivet and adhesive layer, as well as the damage and strengthening mechanism of CFRP/aluminum alloy structure are analyzed. The mechanism of electromagnetic self-piercing riveted-bonded hybrid connection is revealed. The performance and failure behavior of the joint under actual service conditions are studied. The coupling failure mechanism between rivet and adhesive layer is revealed. The service life model of joint is established. The research results will further improve the theoretical basis of dissimilar material joining technology. It will provide method support for the development of reliable performance of riveted-boned hybrid joining technology, and contribute to the development of lightweight automotive manufacturing in China.