Effects of the orientation of magnetostrictive nickel strip on torsional wave transduction efficiency of cylindrical waveguides

摘要

Magnetostrictive transducers are receiving growing attention as an alternative to piezoelectric transducers in generating guided torsional waves in cylindrical waveguides. A recent study shows that torsional wave generation is possible if a set of thin magnetostrictive nickel strips are bonded to the surface of a cylindrical waveguide at an oblique angle and a combination of static and dynamic magnetic fields is applied to the strips. The objective of this work is to experimentally investigate the intriguing effects of the angle on the transduction efficiency and to provide a physical explanation for the observed phenomena. Excitation frequencies used for wave experiments were between 40 and 100 kHz, for which the highest transduction was observed.