A numerical approach to optimize the toolpath strategy for polymers forming

Incremental sheet forming is a relatively new technology with a deformation strategy that resembles the layered manufacturing principle of rapid prototyping; thanks to this, it can represent a viable way to form metal and polymer sheets, guaranteeing high customization and cost-effectiveness. On the other hand, and particularly when considering thermoplastic sheets, the components obtained by this process suffer from peculiar defects like, for example, twisting and wrinkling. A way of reducing the risk of such defects is to optimize the toolpath strategy to lower in-plane forming forces. To pursue this aim, the present work follows a numerical approach; a commercial FE code was used to simulate the incremental forming of polycarbonate sheets by varying the toolpath strategy. The investigation of some features like the forming forces and the deformation states was carried out, with the goal of determining an optimized toolpath strategy for the reduction of the incremental forming forces and the consequent expectation of reduced risk of failures and defects for incremental formed polymer sheets.