Improvement of the dimensional accuracy and machines service life in sheet metal forming by control systems based on MR fluids

Dynamic phenomena in metal forming operations represent a critical aspects for geometrical accuracy of products and service life of parts in high-tech forming machine sector. Stiff presses allow high repeatability and dimensional accuracies, but determine excessive deterioration of tools by stresses and wear; softer ones improve the efficiency and the service life of tools, with higher energy dissipation and bigger scatter in product dimensions. On these bases, the use of SMART devices in forming machines can represent the right trade-off solution for the closed-loop control of dynamic effects. The paper presents an innovative concept for the vibration control in blanking operations, based on the implementation of magneto-rheological (MR) fluids. A new approach focused on a multi-physics optimization analysis is presented which proves to be suitable to investigate the mutual metal-MR fluid interactions and to provide a reliable tool for the design and optimization when different physic fields are involved.