Design principles of additively manufactured multi-material blank holder systems for adaptive pressure control in paper deep drawing

Abstract Paper-based packaging is increasingly used as a sustainable alternative to plastic packaging. However, wrinkle formation during paper deep drawing remains a major challenge due to the low flowability of paperboard and its high degree of anisotropy. Since wrinkle formation is strongly influenced by local material flow, effective process control requires locally adjustable blank holder forces, which are not achievable with conventional blank holder systems. This study presents the design and functional investigation of an additively manufactured multi-material blank holder system for adaptive local pressure control in deep-drawing of paper. The system combines pneumatically actuated flexible pressure pockets with stiff polymer parts to enable spatially adjustable pressure distribution. Finite element simulations and experimental investigations were conducted to analyse the deformation behaviour, pressure transmission and influence on wrinkle formation. The study demonstrates the potential of additive manufacturing for function-integrated tooling systems and derives design principles for adaptive blank holder architectures in forming processes for anisotropic sheet materials. Furthermore, the lateral constraint of the flexible structures improves pressure homogeneity and force transmission. For the use case of paper deep drawing, the results show that localised pressure application significantly affects local material flow.