Contact Conditions and Temperature Distribution During Cryogenic Deep Drawing with Macro-structured Tools

In this paper, the process model for cryogenic forming with macro-structured tools is analyzed regarding the continuously changing thermal conditions during the deep drawing process. For this purpose, the transient contact conditions within the macro-structure are investigated for different tool designs of the macro-structure as a function of the immersion depth and resulting contact pressure in a numerical analysis. The determination of the heat transfer coefficient between the aluminum sheet metal and the tools as a function of the contact pressure is carried out experimentally. Numerical investigations are used to determine an improved macro-structure in terms of low-heat flow and reliable suppression of wrinkling. The influence of the tool design on the temperature distribution is presented and compared with the conventional deep drawing process.