Influence of alternating bending on springback behavior of parts in deep drawing process with macro-structured tools

Abstract

In today’s industry, waste prevention and an efficient use of resources are becoming more important due to economic and environmental requirements. Especially in forming processes such as deep drawing, a reduced use of lubricants is highly promising for saving resources and reducing production costs. Deep drawing with macro-structured tools is a novel approach to reduce the amount of friction forces and realize a lubricant free process. The induced alternating bending in sheet metal during the deep drawing process with macro-structured tools leads to an increase of its geometrical moment of inertia and consequently stabilizes the sheet against wrinkling. The induced alternating bending increases the back force in the sheet metal during the process and as a result affects the springback behaviour of the formed part. Furthermore, the resulted cyclic loading in flange area can leads to a kinematic hardening of some material. Within the scope of this paper, the influence of alternating bending on springback behaviour of parts in deep drawing process with macro-structured tools is studied. For this purpose, numerical simulations as well as experimental tests to form a U-channel with macro-structured tools are carried out.