The target of this research study was to evaluate the shear-tensile and fatigue behavior of aluminum 6061 alloy welds, in two different heat treatment conditions, joined by the recently developed intermediate layer friction stir spot welding (FSSW) technique. The keyhole, which is the disadvantage of the conventional FSSW process, was avoided using an additional intermediate layer (IL) accompanied by a simple tooling. Shear-tensile experiments demonstrated acceptable mechanical performance of IL-FSSW joints in comparison with that obtained using alternative methods. Fatigue behavior of the joints revealed a dependency to pre-processing temper especially at high cyclic load levels with improved life for the aged condition. Observations on the failure regions under shear-tensile experiments exhibited plug type and shear-plug type fracture modes for the aged and annealed conditions, respectively. In contrast, the fracture mode showed variation with respect to the load level but not to the type of temper during cyclic loading.

这项研究的目标是评估铝6061合金焊缝在两种不同的热处理条件下的剪切拉伸和疲劳行为，并结合最近开发的中间层摩擦搅拌点焊（FSSW）技术。锁孔是传统FSSW工艺的缺点，可通过使用附加的中间层（IL）以及简单的工具避免使用。剪切拉伸实验表明，与使用其他方法相比，IL-FSSW接头具有可接受的机械性能。关节的疲劳行为显示出对预处理回火的依赖性，特别是在高循环载荷水平下，具有改善的老化寿命。在剪切拉伸实验下对破坏区域的观察分别显示了在时效和退火条件下的塞型和剪塞型断裂模式。相反，在循环加载过程中，断裂模式显示出相对于载荷水平的变化，而不是回火的类型。