Laser-Ultrasonics Wave Generation and Propagation FE Model in Metallic MaterialsA. Cavuto, G.M. Revel , M. Martarelli , F. Sopranzetti 
Università Politecnica delle Marche, Ancona, Italy
Università e-Campus, Novedrate (CO), Italy
A 2D axisymmetric model was considered in order to evaluate the propagation paths of the ultrasonic waves generated inside an aluminum plate sample due to a rapid thermal expansion produced by laser pulse. Laser Doppler Vibrometer is used to experimentally validate the numerical results of the wave propagation in the material. The presented numerical model is able to identify directivity patterns for the longitudinal (P), transverse (T) and superficial (S) waves. In Non-Destructive Testing (NDT) by Laser Ultrasonics, the development of models that identify the propagation paths of the ultrasonic waves is necessary to establish criteria that allow the defects identification especially in materials with complex shapes such as railway axles.