A new analytical model for force prediction in incremental sheet forming.

A new analytical model for forming force prediction in the whole process of incremental sheet forming (ISF) is presented in this work. The modelling of contact region, thickness distribution and strain components are carried out as the basis for the prediction of vertical and horizontal forces. The effect of local contact behaviour and material deformation, as well as the behaviours of global bending, changes of deformation mode and contact condition are taken into account in the modelling of ISF force history. The force prediction model at both plane strain and biaxial tension condition areas is developed based on the differences in contact region and thickness distribution between these two different deformation states. Validated by ISF tests for a truncated cone and pyramid part with varying drawing angles, the prediction of force history captures well the fluctuation of different force components due to the change of deformation conditions and provides an insight into the material deformation mechanisms and the direct correlation to forming force characteristics of the whole ISF process. In a practical case, the model is successfully applied to the force prediction in ISF-based cranial plate manufacture. The model is also validated by a series of ISF tests with accurate force predictions of both the peak and stabilised forces. [Display omitted] • A new force prediction model with consideration of complicated deformation in ISF. • Forming force history of the whole ISF process. • Demonstration of a direct correlation between ISF forces and deformation states. • ISF force dependency on local contact, deformation, and global bending. • Comprehensive and accurate force prediction in ISF. [ABSTRACT FROM AUTHOR]