WAVESPEEDS MEASUREMENTS IN ANISOTROPIC MATERIALS BY USING LASER GENERATED ULTRASOUND - Archive ouverte HAL
Article Dans Une Revue Journal de Physique IV Proceedings Année : 1992

WAVESPEEDS MEASUREMENTS IN ANISOTROPIC MATERIALS BY USING LASER GENERATED ULTRASOUND

Bernard Castagnede
  • Fonction : Auteur
  • PersonId : 833885
  • IdRef : 052454088

Résumé

Wavespeed measurements made on the quasi-longitudinal (qL) mode have been achieved in two composite materials (i.e. a 1-D glass/epoxy and a 2-D SiC/SiC) by using a correlation algorithm between the measurement signal at a given observation angle, and a reference signal recorded at normal incidence. The wavespeed measurement at normal incidence is obtained, when possible, by correlating the direct qL ray with the 3qL multiple reflection. The qL wavespeeds measured by the laser method are then compared to the phase velocities acquired by standard ultrasonics techniques. The agreement is quite acceptable in most cases. When dealing with laser generated ultrasound, the wavefront of any given ray is propagated at the group velocity. The correlation measurements, should provide wavespeeds which tend to be close to such ray surface velocity. However, the difference between the two wavespeeds is small on the qL mode (generally less than 10 %) and can be as a first approximation safely ignored.

Domaines

Articles anciens
Fichier principal
Vignette du fichier
ajp-jp4199202C1173.pdf (176.93 Ko) Télécharger le fichier
Origine Accord explicite pour ce dépôt
Loading...

Dates et versions

jpa-00251134 , version 1 (04-02-2008)

Identifiants

Citer

Bernard Castagnede. WAVESPEEDS MEASUREMENTS IN ANISOTROPIC MATERIALS BY USING LASER GENERATED ULTRASOUND. Journal de Physique IV Proceedings, 1992, 02 (C1), pp.C1-793-C1-796. ⟨10.1051/jp4:19921173⟩. ⟨jpa-00251134⟩

Collections

CNRS AJP
48 Consultations
75 Téléchargements

Altmetric

Partager

More