Ultrasonic nondestructive evaluation of cylindrical components by resonance acoustic spectroscopy

Potential applications of Resonance Acoustic Spectroscopy (RAS) for the purpose of Nondestructive Evaluation (NDE) of isotropic clad rods and transversely isotropic cylinders encased in a solid elastic medium are investigated in this thesis. Mathematical models are developed for: (1) scattering of an obliquely incident plane acoustic wave from a transversely isotropic cylinder encased in a solid isotropic matrix and (2) scattering of a normally incident plane acoustic wave from an immersed isotropic clad rod with imperfect adhesion between the core and cladding. In these mathematical models, the scattered pressure field is obtained using a normal-mode expansion method. Experimental measurements of the scattered pressure fields are carried out using the short-pulse Method of Isolation and Identification of Resonances (MIIR). The method is applied to: copper-clad aluminum rods made from explosive welding and fiber-reinforced composite rods embedded in a solid medium. The experimental results show good agreement with the results obtained from the mathematical models. It is concluded that RAS has potential applications for nondestructive evaluation of various cylindrical components.