Approach for Improving the Sensitivity of Barkhausen Noise Sensors with Applications to Magnetic Nondestructive Testing

Barkhausen noise emissions occur in ferromagnetic materials on application of a time varying external magnetic field. These emissions primarily occur because of the movement of domain walls in the presence of pinning sites or discontinuities, which act as inhibitors to domain wall motion within the material. The emissions can be sensed using an induction coil placed close to the sample surface. The coil can sense the variations in magnetic flux, which translates to the induced electromagnetic field. This study optimizes the design of the barkhausen noise sensor via finite element simulations. The different parameters involved in improvement of the design of the barkhausen noise sensor are discussed.