Experimental Study on the Wave Mode in Elastic Cylindrical Rod

Abstract

Experimental study on the high frequency elastic wave mode propagating in a long circular aluminum rod was executed using new devices. A four terminals type piezo-electric transducer was used to observe the phase of vibration of each mode at the end of the rod and to classify directly the wave modes. Experimental results are as follows. Good coincidence between the theoretical group velocity and the experimental propagating velocity in each mode is obtained within the experimental errors. The mode coupling phenomenon is observed at the critical frequency, and also observed in the condition of the F2 mode type impulse. The directions of the neutral surface of vibration in the F1 modes are different from each other. The directions in the F1(2) mode and the F1(3) mode are perpendicular and parallel to the direction in the F1(1) mode respectively, and each direction does not change with a change of frequency.