Conversion of Ultrasonic Waves with Symmetric Notches in Isotropic Plate

Lamb waves are ultrasonic technic usedto control the quality of mechanical parts and to monitor their integrity statebefore their entire fracture. In this paper, we aim to study the ultrasonicpropagation theory and numerical simulation in Aluminum plate. Firstly, the twoanalytical equations of the symmetrical and anti-symmetrical lamb modes arecalculated numerically by MATLAB algorithm based on the SAFE (Semi AnalyticalFinite Element Method) to compute the dispersion curves: wave number and phasevelocity in function of the frequency - thickness (f.e). Secondly, simulations werecarried out using ABAQUS CAE based on Finite Element Method (FEM) toinvestigate the propagation and the interaction of lamb modes by defect typenotches. Thirdly, the propagating modes are identified using two-DimensionalFast Fourier Transform (2D-FFT).