Abstract: A method comprises magnetizing a portion of the test piece by a pulsed magnetic field and forming as a result of said magnetizing two regions of remanent magnetization, which are magnetized to saturation in opposite directions, determining the magnitude of the remanent induction, which magnitude is used to judge the mechanical properties of the test piece. The magnitude of the remanent induction is determined by converting its gradient along the magnetized portion to an electrical signal, selecting from said signal a one-polarity pulse indicative of the change in the remanent induction between said regions, and integrating said selected pulse. A device comprises a pulse generator 1, magnetizing coils 2 connected to said generator in antiparallel relationship and arranged along the test piece, a transducer 4 for converting a gradient to an electrical signal, a measuring circuit including a key 5 and an integrator 6.