Magnetostriction and magnetic forces in electrical steel: finite element computations and measurements

The experimental determination of the magnetoelastic characteristics of ferromagnetic materials by means of strain gauges and the computation of the deformation due to magnetic forces and magnetostriction by using the finite element method are presented. For measuring the magnetoelastic properties of electrical steel sheet, a small single sheet tester has been build. The measurement setup has been simulated by means of the two-dimensional finite element method. Two geometries of the steel samples have been considered, namely with and without an airgap. The difference between the measured strain in the sheet with and without the airgap (due to the so-called form effect) closely agrees with the simulation results.