Shear Modulus Measurement Using Torsional Ultrasonic Pulses

An ultrasonic method of measuring shear modulus of solids is investigated. The method makes use of torsional ultrasonic pulses with a magnetostrictive transducer. Shear modulus is calculated according to the density of the material to be tested and the measured propagation speed of the ultrasonic pulse in the speciment to be tested. Measuring principle, system composition, design of the magnetostrictive torsional wave ultrasonic transducer and the measuring uncertainty are discussed. The moduli of three different types of materials have been measured with an experimental measurement system composed of a magnetostrictive torsional wave ultrasonic transducer, a general-purpose pulsar/receiver and an electronic oscilloscope. Experimental results showed that the method investigated is an effective way to measure the shear modulus of solids quickly and accurately.