A new approach to measure the ultrasonic attenuation and hence characterisation of materials has been made. The method requires the test sample in the form of a cylindrical rod of different end diameters. A broad band transducer is coupled to the curved surface of the rod through an appropriate couplant. The transducer is excited by a short duration negative spike. Frequency spectrum analysis of the first three echoes for both of the ends of the rod is used to evaluate the ultrasonic attenuation.

A single probe generating and receiving the longitudinal waves is capable of measuring both longitudinal and shear wave attenuation simultaneously. Results are presented for ultrasonic attenuation in various materials in the frequency range 2 MHZ to 6 MHZ. The values obtained are comparable to the results obtained earlier with other techniques and in the literature. Minimum and maximum values for the diameters of the rod are also evaluated for the materials under study.

The new approach does not require the correction for beam diffraction or for coupling condition which are necessary for all other known methods. Method is simple to use and requires only one transducer of center frequency around the middle of the frequency range of interest. Little change in experimental setup is required to make measurements at different temperatures.