Fermeture et ouverture de fissure de fatigue : détection et mesure par une méthode ultrasonore

Detection and measurement of fatigue crack by an ultrasonic method

Section Ultrasons, Laboratoire Matériaux, Ecole Centrale des Arts et Manufactures

Abstract

In order to assess fatigue crack propagation, one of the most used law is due to Elber. This involves, however, accurate measurement of the opening load of the crack which is closed at its tip. We propose a new ultrasonic method based on wave diffraction by crack tip and record of echodynamic. It detects and measures accurately both closure and opening of crack (corresponding length and loads). It is able to do that both near the lateral faces and in the bulk of the specimen. It is well suited to thick CT specimens.