Rate-dependent constitutive model for sheet metal blanking investigation

Ferromagnetic sheet metal blanking is widely used for the manufacturing of rotating electrical machines. As the blanking process deeply affects the material mechanical state near the cut edge, it also involves degradations of magnetic properties like loss of permeability. In this context, full understanding of the shearing process is needed and a predictive model can be helpful for the design of rotating electrical machines. With such a model, the designer can easily assess the influence of the blanking process parameters on the reliability of the designed machines. For this purpose, the constitutive equation used for the blanking process modelling is a key point since accurate predictions are required. In this paper, a rate-dependent constitutive model for the blanking process investigation is used to improve the accuracy of the predictions. Material testing and characterization are carried out in order to fit the constitutive model parameters to experimental data. The identified model is then used for numerical simulation of various blanking tests and the obtained numerical results are compared with measurements for validation purposes. The strain rate effect was found to be relevant for the blanking process.