Coatings are widely used in industrial applications,such as surface protection from corrosion,friction,oxidation,etc.The elastic properties of the coating materials play a vital role in the performance of these structures and devices.Thus,this paper focuses on the determination of elastic parameters of coatings from the ultrasonic measurements of dispersion curves by acoustic microscopy.V(f,z)analysis will be applied on the numerous defocusing measured data to extract the dispersion curves.