Outwards and inwards crimping of tube ends by single-point incremental forming

摘要

Tube end forming is a frequently used approach in the production of tubular parts. Traditional tube end forming is conducted on press with dedicated punch and die. The current study examined a new method for crimping open tube ends based on the single-point incremental sheet forming technology. Al 6061 tubes with outer diameter of 38 mm and thickness of 1.0 mm were employed in the study. The results proved that outwards/inwards crimping of open tube ends can be accomplished utilizing this flexible method. Tube wall deformations are dominated by the combination of processing parameters, especially the feeding path and tool geometry. Compared with the integer formation of press working, though incremental tube end crimping has smaller axial load during forming, instability phenomena of the wall are prone to take place due to the localized and asymmetrical action of the tool, and the absence of die constraint as well.