钢铝板材压-胶复合连接性能

为提高钢铝混合轻量化车身结构中钢和铝异种材料的连接性能,对钢铝板材的压-胶复合连接技术进行仿真与实验研究.以A5052铝合金板和Q235钢板为被连接件,环氧树脂为胶粘剂,采用内聚力模型模拟胶层的失效行为,建立压-胶复合连接的剪切和剥离仿真模型.在实验验证仿真模型有效性的基础上,基于响应面近似模型对连接工艺参数进行多目标优化,得到关于剪切强度和剥离强度的Pareto前沿解集以及各参数的优化组合.结果表明:优化解集中的多个工艺方案均能保证连接点剪切强度在9 400 N以上,而剥离强度均在700 N以上.实验证明钢铝板材压-胶复合连接强度比无胶单独的压力连接提高一倍以上,且可以达到同条件下钢板焊接拉伸强度的80%左右.

Performances of clinch-bonded hybrid joints between steel-aluminum sheets

To improve the connection performances of steel-aluminum hybrid lightweight car-body structure, the clinch-bonded hybrid joint technology between steel and aluminum were researched by simulation and experiment. With the A5052 aluminum alloy and Q235 steel as the connected elements and epoxy as the adhesive, cohesive zone model simulating the damage behavior of the adhesive was applied to build up the shear and peel simulation model of the clinch-bonded hybrid joint. On the basis of the experimental verification of the simulation model and multi-objective optimization set by the RSM model for the connection parameters, a Pareto solution about the shear strength and peel strength as well as the optimization combination of the parameters were gained. The results show that the multiple schemes in the optimization solution can ensure the shear strength above 9 400 N, and the peel strength above 700 N. Experiments confirm that the strength of clinch-bonded joints can be twice or more as the sole clinch joint without adhesive, and it can reach 80% of the weld tensile strength of steels under the same conditions.