Effect of Material Properties of 3D-printed Plastic forming Tools on Micro-stamping of Bipolar Plates

Abstract Additive manufacturing offers a cost-effective route for rapid prototyping of micro-forming tools, but the reduced stiffness and strength of polymer tools can significantly affect forming accuracy. This study investigates how tool material properties influence micro-stamping of channels relevant to metallic bipolar plates for hydrogen fuel cells. Micro-stamping experiments were conducted using 3D-printed polymer tooling, and tool and channel profiles before and after forming were measured using optical surface profilometry. These measurements were used to validate a finite element model capable of predicting coupled sheet deformation and tool compliance. Following validation, additional polymer materials were implemented in the model to evaluate material effects systematically. Results show that forming accuracy is governed by tool compliance, which alters the effective tool–sheet gap during forming. A high-stiffness glass-reinforced resin (Rigid 10K) exhibited negligible permanent deformation and produced channel geometries closest to the target profile, demonstrating the importance of tool mechanical properties in micro-forming design.