ABSTRACT

This paper introduced a hybrid joining system including friction stir spot welding (FSSW) and adhesive bonding, named friction stir spot weld bonding (FSSWB). In order to avoid adhesive layer carbonization, FSSWB was processed by flow-in method. The aim of this study was to evaluate the effect of adhesive ductility and joint configuration on the tensile-shear performances of AA6061 aluminum alloy. Two types of adhesives were considered: brittle epoxy (AV138) and ductile epoxy (Araldite 2015). Besides, hybrid joints involve three types of joint configurations (AV138, Araldite 2015 and dual adhesive). A finite element (FE) model of hybrid joints failure process was established based on the extended finite element method (XFEM) and cohesive zone model (CZM). The tensile-shear failure load (TSFL) prediction values and joint failure process were in good agreement with the experiments. Compared to FSSW, the TSFL values for the three types of hybrid joint increased by 166.5%, 294.8% and 173.8% respectively. In addition, the stresses at the hook tip of the three hybrid joints were decreased by 85.56%, 79.31% and 83.67%. From the study, it was found that the use of ductile adhesives at two sides of joint was more helpful to increase the load-bearing capacity of FSSWB joints.

摘要

本文介绍了一种包括搅拌摩擦点焊（FSSW）和粘合剂粘合的混合连接系统，称为搅拌摩擦点焊（FSSWB）。为了避免胶层碳化，FSSWB采用流入法加工。本研究的目的是评估粘合延展性和接头配置对 AA6061 铝合金拉伸剪切性能的影响。考虑了两种类型的粘合剂：脆性环氧树脂 (AV138) 和韧性环氧树脂 (Araldite 2015)。此外，混合接头涉及三种类型的接头配置（AV138、Araldite 2015 和双胶）。基于扩展有限元法（XFEM）和内聚区模型（CZM）建立了混合接头失效过程的有限元（FE）模型。拉伸剪切破坏载荷（TSFL）预测值和接头破坏过程与实验非常吻合。与FSSW相比，三种混合接头的TSFL值分别提高了166.5%、294.8%和173.8%。此外，三种混合接头的钩尖应力分别降低了85.56%、79.31%和83.67%。研究发现，在接头两侧使用延性粘合剂更有利于提高 FSSWB 接头的承载能力。