Magnetoelastic demagnetization of wires and foils made of ferromagnetic materials is studied during cyclic mechanical tests. The behavior of the magnetic properties of the 30Kh13 and 30K4MVI steels allowing their use in foil or wire design as magnetic transducers of strains in structures and structural components is revealed. Sensors of this type can be more highly sensitive than tensoresistive ones, they are wireless, less time-consuming to install, and more cost-effective.