Increasing the LDR through additional radial compressive stress

A new deep drawing process variant with additional radial compressive stress has been developed and analyzed, which generates a flow of material from the outer part of the flange toward the developing cup, and therefore improves the formability and increases the limiting drawing ratio (LDR). If the deep drawing process is executed with the correct time characteristic, no “cup-base fracture” will occur as known from the conventional deep drawing process. In order to establish the prerequisites for a scientific founded technological lay-out of that new process the influence of different relevant process parameter were analyzed, and the achievable properties of the final parts and the process limits of that new deep drawing variant were determined.