Analysis and elimination of the stretcher strains on TH415 tinplate rings in the stamping process

Deep drawing process, although deceptively simple, involves a complex interplay between material properties, die geometry and process variables. The process optimisation is at the same time often affected by visual and design demands of a final product. The annealed low carbon steels used for tinplate rings, often undergo the strain hardening with extended yield point (yield point elongation) that results in surface defects of the formed part—the so-called stretcher strains (connected with Lueders’ bands phenomenon). This paper presents the finite element analysis of tinplate rings with ABAQUS program in order to analyse the phenomenon of the stretcher strains on an industrial case study. Numerical results were compared with the measured deformation of the stamped part. Finally the geometrical part optimisation was implemented in order to reduce the area with stretcher strains to a technologically attainable minimum.