Centre National De La Recherche Scientifique

Snecma

Cnrs

Centre National De La Recherche Scientifique-cnrs

Pierre-Yves Joubert

Dominique Placko

Alain Rivollet

Michel Bernard Lemistre

Yann Le Bihan

Jean-Marc Decitre

Yohan Le Diraison

Jamal Ben Youssef

Jean Pinassaud

Francois Lepoutre

Olivier Lespinet

Aleksandra Mikic

Alexandra Mikic

The invention relates to a device and method for estimating defects potentially present in an object comprising an outer surface, wherein the method comprises the steps of: a) illuminating the outer surface of the object with an inductive wave field at a predetermined frequency; b) measuring an induced wave field ({right arrow over (H)}) at the outer surface of the object; c) developing from the properties of the object's material a coupling matrix T associated with a depth Z of the object from the outer surface; d) solving the matrix system to determine a vector ({right arrow over (J)}) at depth Z; e) extracting a sub-vector ({right arrow over (J)}) from the vector ({right arrow over (J)}) corresponding to a potential defect on the object at depth Z; and f) quantitatively estimating the potential defect from the sub-vector ({right arrow over (J)}) at depth Z, wherein the method is performed using a computer or processor.

Method for estimating defects in an object and device for implementing same

This eddy current imaging method includes the steps of:

Method and device for eddy current imaging for the detection and the characterisation of defects hidden in complex structures

A method for evaluating the wall thickness of a hollow part, of the turbomachine blade type, at least at a point having a determined radius of curvature at this point, within determined ranges of radii of curvature and thicknesses, including the determination of impedance values of an electrical circuit formed by an eddy current detector applied to the wall, and the insertion of these values into a digital processing unit with a neural network, wherein the network parameters have been defined in advance by learning on spacers having a determined radius of curvature and thickness in the ranges.

Measurement of wall thicknesses particularly of a blade, by eddy currents

A quantitative magneto-optical imaging method is used to form an image of a target material. An active material is placed close to the target material and produces a Faraday rotation in a polarized light beam. The Faraday rotation of the active material is essentially proportional to the magnetization of the target material when this latter is subjected to an exciting magnetic field. Photodetector means detect the beam reflected after passing through the active material. The light from the reflected beam can then be analyzed for obtaining the amplitude and phase of an interfering magnetic field generated by a defect in the target material.

Magneto-optical imaging method and device

Growing community of inventors

Sceaux, France

Pierre-Yves Joubert