Ultrasonic bridge for simultaneous measurements of wave speed and attenuation

A technique is described for simultaneous velocity and attenuation measurements in the monitoring of material properties. To determine the attenuation, the amplitudes of tone-burst signals generated over a wide frequency range have been measured. For the determination of the wave velocity, a number of frequencies are selected at which a zero crossing of the tone-burst signal coincides with a zero crossing of a continuous reference sinewave. A self-calibrating technique for simultaneous measurements of wave speed and attenuation has been employed in conjunction with a recently developed ultrasonic bridge. An application of the technique is described