An experimental investigation on the dissimilar joining of AA6061 and 1Cr18Ni9Ti by refill friction stir spot welding and its mechanical properties

作者：Qiao, Fengbin^*; Cheng, Kai; Wang, Lianfeng; Guo, Lijie

来源：Proceedings of the Institution of Mechanical Engineers - Part B: Journal of Engineering Manufacture , 2016, 230(4): 779-785.

DOI：10.1177/0954405415603599

• Dissimilar joint
• refill friction stir spot welding
• microstructure
• shear strength
• friction stir spot welding

This article presents an industrial feasible approach to robustly joining dissimilar materials of AA6061-T6 and 1Cr18Ni9Ti using refill friction stir spot welding processes and the associated joints assessment. The microstructure and shear strength property tests are taken on the dissimilar joints of 2-mm-thick plates. The results indicate that the microstructure change of the joints can be categorized in stir zone, heat-affected zone, thermomechanically affected zone and base material. The 1Cr18Ni9Ti material is squeezed toward the 6061-T6 material and forms the hook tissue, which enhances the mechanical properties of the refill friction stir spot welding-enabled joints of two dissimilar materials. The shear strength of the joints increases at first and then decreases with increase in the tool rotational speed, the indentation depth, the axial force and welding time. When the welding process is carried out at the tool rotational speed of 1800r/min, indentation depth of 2.3mm, the axial force of 15.65kN and the welding time in 7.5s, the maximum shear strength of the joints can be achieved as being able to take the loading of 8650N as experimentally tested.

• 出版日期2016-4
• 单位同济大学