Joining different aluminum alloy sheets by flat clinching process

Increasing attention has been paid to the flat clinching process for constructing advanced engineering structures because it has more benefits than the conventional cliching process. The effect of material arrangements on flat clinching process was investigated in the paper. The four material arrangements using three dissimilar aluminum alloys were employed to develop flat clinching joints. The cross-sectional profile of the joint was observed, and its main geometrical parameters were determined. The mechanical characteristics of the joint include four parts: tensile strength, shearing strength, failure mode, and absorbed energy. Tension-shearing and tensile tests were carried out to assess the mechanical characteristics of the flat clinching joint. The geometric profile and the material properties determine the mechanical characteristics of the flat clinching joint. Compared with the flat clinching joint using a hard lower sheet, the flat clinching joint with a hard upper sheet demonstrates a larger neck thickness and a lower undercut. Meanwhile, it has greater static strength and absorbed energy. In tension-shearing tests, necking failure is only failure mode appearing; in tensile tests, failure mode mostly belongs to unbutton failure. The flat clinching process can effectively join dissimilar aluminum alloy sheets.