Integrated Magnetic imAgery
based on spIntronics Components
IMAGIC aims at developing a new integrated magnetic imagery based on highly sensitive arrays of spin electronics based magnetic sensors that allow a very good spatial resolution, to improve the performances of the Eddy Current method of non destructive testing. The objective is to lead developments to the industrialization of smart systems combining technological developments with sophisticated treatment tools.
Spin electronics magnetic sensors developed in this project are very sensitive giant magnetoresistive sensors (GMR) or tunnel magnetoresistive sensors (TMR) designed in order to be very sensitive in a frequency range of 100Hz to 5MHz with a very low noise at low frequencies.
Eddy current non destructive evaluation is applied on metallic objects. A variable homogeneous magnetic field is applied on the object, creating eddy currents to reduce the penetration of this magnetic field inside the metallic object. This currents are flowing perpendicularly to the applied field. If a defect like a dislocation or a hole is present, the current lines are deviated. These lines are themselves creating a field and the imaging of this field allow us reconstructing the current lines and hence discovering the presence of a defect.
Field created by a small defect of 100x100x50µm3 detected by a GMR sensor. The measured field is perpendicular to the emitted field