8 - Micromagnetic nondestructive testing Barkhausen noise vs other techniques

Abstract

This chapter provides a review of the micromagnetic nondestructive testing and evaluation techniques. We will focus, in particular, on the well-established magnetic Barkhausen noise (MBN) technique. The use of the MBN as an NDT method has extensively increased recently in the industrial field mainly due to the improvement of the signal processing techniques which have allowed online production monitoring. The success of these methods relies on the magnetic signature of ferromagnetic steels, which are highly dependent on the mechanical and microstructural properties of the material. Up to now all these methods are based on scanning processes and rejection thresholds but progresses in simulation open the way to predictive behavior. In this chapter, the main and/or the most promising micromagnetic NDT&E techniques are introduced, large part will be devoted to MBN. Some simulation aspects will be discussed and a conclusion on which method is the most adapted to a given defect will be established.