Effect of Backing Materials on the Performance of Cement-Based Piezoelectric Ultrasonic Sensors

Abstract

In order to increase the sensitivity, frequency bandwidth and longitudinal resolution of the 1-3 cement-based piezoelectric ultrasonic sensor, different metal powder/epoxy resin composite materials were used to make backing layer, and the performances of sensors were evaluated and compared. The results indicated that the increase of the sensitivity and the frequency bandwidth, as well as a decrease of the pulse wave number can be observed when the backing materials of metal powder/epoxy resin composite materials were added to the sensor. A 42%-increase of the maximum peak-to-peak value of the echo pulse response, a 52%-reduction of the ring down time and a 200%-increase of the bandwidth can be achieved by using the backing material.