Method of fault detection by focusing ultrasonic waves generated by laser pulses

摘要

The present invention relates to a method (P) for detecting a defect in a region of interest of a part comprising the following steps: (P1) illumination of a surface of the part by a laser pulse having a suitable spatial profile for generating an ultrasonic wave focusing in the region of interest; (P2) acquiring a measurement signal of the ultrasonic wave focused in the region of interest; the laser pulse being adapted to generate an effect nonlinear on the ultrasonic wave if the defect is present in the region of interest, the method further comprising a step: (P3) of comparing the measurement signal with a reference signal, the reference signal comprising an estimate of d a signal acquired from an ultrasonic wave focused in the region of interest when the region of interest does not contain a defect. Figure for the abstract: Fig. 5