Performance evaluation of topology optimized and additive manufactured punch holders for blanking operation–a case study

This study employs the Evolutionary Structural Optimization (ESO) algorithm, integrated with finite element analysis, to optimize the topology of a conventional punch holder. The punch holder's dimensions were reverse-engineered using a 3D scanner, and the actual punch force required for copper material was calculated as 2.434 kN. Topology-optimized punch holders were fabricated using fused deposition modeling technique with three different material options (ABS, PETG, and PLA). Compared to conventional metal punch holders, weight reduction was significant, with values of 7.59%, 7.62%, and 7.60% for PETG, PLA, and ABS, respectively. Mechanical analysis revealed notable performance improvements as PETG showed a 5.7% increase in equivalent strain and a 175.8% rise in strain energy, while ABS exhibited a 6.0% rise in strain and a 69.4% decrease in deformation, indicating enhanced stiffness. The optimized punch holders also resulted in superior forming performance, successfully handling 50 punch trials without any defects. These findings show that ESO reduces material use while enhancing mechanical efficiency and durability, advancing the application of additive manufacturing in the blanking process, particularly for small-batch customized and lightweight punch holders.