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In order to eliminate residual stresses in the welds of thin-sheet non-magnetic metals, the possibility of using magnetic pulse processing is considered. An electromagnetic inductor with a U-shaped magnetic circuit and two coils of solid conductor is considered. To create a unipolar current pulse in the inductor winding, a trinistor is used, which switches the electrical circuit from the capacitor, inductance and active resistance, and when the current in the inductor winding reaches zero, the circuit opens. The calculation of the transient process in an electric circuit with a dynamically changing inductance is performed by solving a circuit-field problem with given initial conditions. The calculation of the electromagnetic field is performed by the finite element method for a two-dimensional model of the inductor. The study of electromagnetic processes in the inductor and thin-sheet non-magnetic workpieces with the amplitude of the maximum current density of 1 kA/mm 2. The distribution of current density and magnetic force density on the workpiece surface and in time is given. It is proved that only for a small thickness of welded products (2 mm) can be achieved simultaneous power and current.

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Pulsed currents and magnetic forces of an induction system with a spiral winding and a ferromagnetic shield for processing non-magnetic thin-sheet metal strips in order to create magnetoplastic, electroplastic effects due to eddy currents are studied. Under the strip there is the ferromagnetic shield, and above it – spiral winding. The aim of the work is to develop an analytical method for calculating transients of pulsed currents in an electric circuit with the induction system and a capacitor charged to certain voltage taking into account influence of the ferromagnetic shield to perform investigation of time-varying magnetic field. Electromagnetic parameters of the inductor are determined by computer simulation using the finite element method in the mode of harmonic currents. Current transients in the electric circuit are calculated using known in theoretical electrical engineering mathematical dependences and distribution of current density and magnetic forces in the strip is calculated by the finite element method in the mode of transients. Influence of the ferromagnetic shield on electromagnetic processes in the induction system for the set ranges of strip’s thickness, its electrical conductivity and current frequency is established. Electromagnetic force between the spiral winding and the strip, the current density in the strip, as well as the moments of time at which the current and force have maximum values are studied. References 14, figures 6, tables 2.