Electromagnetic forming is a high-velocity process aiming at the shaping of a conducting workpiece with the aid of a strong electromagnetic field. Here, we deal with a hollow cylindrical workpiece made of magnetic and conducting material. A forming coil is placed inside the workpiece, and a high-current pulse is passed through it in order to generate an electro-magnetic field inside the workpiece. Due to the interaction between the electromagnetic field and the induced current in the workpiece, a force is developed, causing the workpiece to expand rapidly, first elastically and then plastically. To obtain the shape of the high-current pulse, an equivalent network model of the investigated electromagnetic forming system is used. For the current pulse obtained with the network model, the transient diffusive electromagnetic field in the workpiece is obtained and the equivalent expansion pressure exerted on the workpiece is calculated. Next, this pressure is used as a mechanical source term for calculating the elastoplastic deformation of the workpiece. This is done using the quasistatic elastodynamic field and a particular model of the elastoplastic behavior of the workpiece material.
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