Present and Future Impact of Magnetic Sensors in NDE

Non Destructive Evaluation (NDE) techniques are widely used in several industries in order to control product quality or to ensure the integrity of a part. A wide variety of methods exist. They involve the application of a suitable form of energy to the specimen under test. One of these forms of energy can be electromagnetic and the most used imply the measurement of a magnetic field.This presentation starts with a survey of today's magnetic field sensing elements. Then, it overlooks the electromagnetic methods used for inspecting materials involving magnetic field measurements. Among these methods are magnetic flux leakage (MFL) and eddy current testing (ECT). Some considerations on different excitation forms like sinusoidal, multi-harmonic, pulsed or transient or even velocity induced are untaken.The presentation concludes with an analysis of the advantages and drawbacks of each class of magnetic sensing technology when applied to an electromagnetic method involving magnetic field measurement. The approach of this presentation follows some of the recent developments in the magnetic sensors technology and studies the present and future impact of the improvements in the nondestructive evaluation methods.