New sensor principles based on Barkhausen noise

More than 85 years after its discovery, the Barkhausen effect remains one of the basic principles involved in the characterization of magnetic and metallic materials, e.g. to measure their residual stresses and hardness. Reliable testing results can be obtained quickly and nondestructively for a large range of industrial applications using micro-magnetic parameters. This paper summarizes the physical principles and demonstrates applications important for today's nondestructive testing procedures.