Time-Domain Ultrasonic NDE of the Wave Velocity of a Sub-Half-Wavelength Elastic Layer

The purpose of this paper is to report a new technique for ultrasonic NDE of the wavespeed of a sub-half-wavelength layer (given its thickness) using only the time-domain information. The new technique was applied to aluminum plates with h λ ranging from 0.082 to 2.0 where h and λ are the plate thickness and the nominal wavelength, respectively. A satisfactory compatison between the measured values and the nominal value was observed.