SCATTERING OF AN OBLIQUELY INCIDENT PLANE-WAVE FROM A CIRCULAR CLAD ROD

The problem of scattering of an obliquely incident plane acoustic wave from an infinite solid elastic clad rod is formulated. Numerical calc ulations show the effects of the variations of the cladding thickness on both the backscattered pressure spectrum and individual normal mode s. It is shown that various resonance frequencies have different level s of sensitivity to variations of the cladding thickness. Experimental measurements are also performed at both normal and oblique incident a ngles on a copper-clad aluminum rod; good agreement is observed betwee n the calculated and the measured results. These results demonstrate t he potential of acoustic resonance scattering procedures for applicati on in nondestructive evaluation (NDE) of clad rods. (C) 1997 Acoustica l Society of America.